business mathematics

Compound Intrest Concept

noreply@blogger.com (Ravi Kumar) — Thu, 15 Sep 2011 11:12:00 +0000

Compound Interest:
Sometimes it so happens that the borrower and the lender agree to fix up a certain unit of time ,say yearly or half-yearly or quarterly to settle the previous account.
In such cases ,the amount after the first unit of time becomes the principal for the 2nd unit ,the amount after second unit becomes the principal for the 3rd unit and
so on. After a specified period ,the difference between the amount and the money borrowed is called Compound Interest for that period.

Formula:

Let principal=p, Rate=R% per annum, Time=n years

1.When interest is compounded Annually,
Amount=P[1+(R/100)]n
2.When interest is compounded Half yearly,
Amount=P[1+((R/2)100)]2n
3.When interest is compounded Quarterly,
Amount=P[1+((R/4)100)]4n
4.When interest is compounded Annually,but time in fractions
say 3 2/5 yrs Amount=P[1+(R/100)]3[1+((2R/5)/100)]
5.When rates are different for different years R1%,R2%,R3%
for 1st ,2nd ,3rd yrs respectively
Amount=P[1+(R1/100)][1+(R2/100)][1+(R3/100)]
6.Present Worth of Rs.X due n years hence is given by
Present Worth=X/[1+(R/100)]n

Simple Intrest Concept

noreply@blogger.com (Ravi Kumar) — Mon, 05 Sep 2011 11:12:00 +0000

Principal or Sum:-
The money borrowed or lent out for a certain period is called Principal or the Sum.

Interest:-
Extra money paid for using others money is called Interest.

Simple Interest:-
If the interest on a sum borrowed for a certain period is reckoned uniformly,then it is called Simple Interest.

Formula:
Principal = P
Rate = R% per annum
Time = T years. Then,

(i)Simple Interest(S.I)= (P*T*R)/100

(ii) Principal(P) = (100*S.I)/(R*T)
Rate(R) = (100*S.I)/(P*T)
Time(T) = (100*S.I)/(P*R)

Oddman Out and Series

noreply@blogger.com (Ravi Kumar) — Tue, 30 Aug 2011 13:56:00 +0000

Introduction:

In any type of problems,a set of numbers is given in such a way
that each one except one satisfies a particular definite
property.The one which does not satisfy that characteristic is
to be taken out. Some important properties of numbers are
given below :

1.Prime Number Series
Example:
2,3,5,7,11,..............
2.Even Number Series
Example:
2,4,6,8,10,12,...........
3.Odd Number Series:
Example:
1,3,5,7,9,11,...........
4.Perfect Squares:
Example:
1,4,9,16,25,............
5.Perfect Cubes:
Example:
1,8,27,64,125,.................
6.Multiples of Number Series:
Example:
3,6,9,12,15,..............are multiples of 3
7.Numbers in Arthimetic Progression(A.P):
Example:
13,11,9,7................
8.Numbers in G.P:
Example:
48,12,3,.....
Some More Properties:

1. If any series starts with 0,3,.....,generally the relation
will be (n2-1).
2. If any series starts with 0,2,.....,generally the relation
will be (n2-n).
3. If any series starts with 0,6,.....,generally the relation
will be (n3-n).
4. If 36 is found in the series then the series will be in n2
relation.
5. If 35 is found in the series then the series will be in
n2-1 relation.
6. If 37 is found in the series then the series will be in n2+1
relation.
7. If 125 is found in the series then the series will be in n3
relation.
8. If 124 is found in the series then the series will be in n3-1
relation.
9. If 126 is found in the series then the series will be in n3+1
relation.
10. If 20,30 found in the series then the series will be in n2-n
relation.
11. If 60,120,210,........... is found as series then the series
will be in n3-n relation.
12. If 222,............ is found then relation is n3+n
13. If 21,31,.......... is series then the relation is n2-n+1.
14. If 19,29,.......... is series then the relation is n2-n-1.
15. If series starts with 0,3,............ the series will be on
n2-1 relation.

Trains Concept in Business Maths

noreply@blogger.com (Ravi Kumar) — Thu, 25 Aug 2011 11:10:00 +0000

(1) Time taken by a train x mt long in passing a signal post or a pole or a standing man = time taken by the train to cover x mt.

(2) Time taken by a train x mt long in passing a stationary object of length y mt = time taken by the train to cover x+y mt.

(3) Suppose two trains or two bodies are moving in the same direction at u kmph and v kmph such that u > v then their relative speed is u-v kmph.

(4)If two trains of length x km and y km are moving in opposite directions at u kmph and v kmph,then time taken by the train to cross each other = (x+y)/(u+v) hr

(5) Suppose two trains or two bodies are moving in opposite direction at u kmph and v kmph then,their relative speed = (u+v) kmph

(6)If two train start at the same time from 2 points A & B towards each other and after crossing they take a & b hours in reaching B & A respectively then
A's speed : B's speed = (b^1/2 : a^1/2 )

Alligation or Mixtures Concept

noreply@blogger.com (Ravi Kumar) — Sat, 20 Aug 2011 11:11:00 +0000

Alligation or Mixtures Concept important points:

1.Alligation:
It is the rule that enables us to find the ratio in which two of more ingredients at the given price must be mixed to produce a mixture of a desired price.

2.Mean Price:
The cost price of a unit quantity of the mixture is called the mean price.

3.Rule of Alligation:
If two ingredients are mixed then
Quantity of Cheaper / Quantity of Dearer = (C.P of Dearer – Mean Price) /(Mean Price–C.P of Cheaper).

C.P of a unit quantity of cheaper(c)
C.P of unit quantity of dearer(d)

Mean Price(m)

(d-m) (m-c)

Cheaper quantity:Dearer quantity = (d-m):(m-c)

4.Suppose a container contains x units of liquid from which y units are taken out and replaced by water. After n operations the quantity of pure liquid = x (1 – y/x)n units.

Partnership Concept

noreply@blogger.com (Ravi Kumar) — Mon, 15 Aug 2011 09:27:00 +0000

Partnership:
When two or more than two persons run a business jointly, they are called partners and the deal is known as partnership.

Ratio of Division of Gains:

1.When the investments of all the partners are do the same time, the gain or loss is distributed among the partners in the ratio of their investments.

Suppose A and B invest Rs x and Rs y respectively for a year in a business, then at the end of the year: (A's share of profit):(B's share of profit)=x:y

2.When investments are for different time periods, then equivalent capitals are calculated for a unit of time by taking (capital*number of units of time). Now gain or loss is divided in the ratio of these capitals.

Suppose A invests Rs x for p months and B invests Rs y for q months, then (A's share of profit):(B's share of profit)=xp:yq

3.Working and sleeping partners:A partner who manages the business is known as working partner and the one who simply invests the money is a sleeping partner.

Formula:

1.When investments of A and B are Rs x and Rs y for a year in a business ,then at the end of the year (A's share of profit):(B's share of profit)=x:y

2.When A invests Rs x for p months and B invests Rs y for q months, then
A's share profit:B's share of profit=xp:yq

Useful Business Mathematics

noreply@blogger.com (Ravi Kumar) — Thu, 11 Aug 2011 07:22:00 +0000

You feel difficult when you are learning this type of maths specially at the age of 11 or 12 years. When i was studying my 6th class, i was first introduced this maths.

Business maths is one of the branches of mathematics just as algebra, geometry, statics. You can also call business maths as arithmetic.

Topics like simple interest, compound interest, percentages, distances will definitely create problems. Even though it is difficult it is useful in real life. When you are buying or selling some goods, you can not calculate your profit or loss if you don't know business mathematics. When it comes to money borrowing from others(generally persons who you don't know), you should know simple interest. otherwise they may cheat you. I too have seen many such cases.

Boats and Streams

noreply@blogger.com (Ravi Kumar) — Sun, 07 Aug 2011 06:58:00 +0000

Important facts:

1)In water, the direction along the stream is called down stream.

2)Direction against the stream is called upstream.

3)The speed of boat in still water is U km/hr and the speed of stream is V km/hr then

speed down stream =U + V km/hr
speed up stream = U – V km/hr

Formulae:

If the speed down stream is A km/hr and the speed up stream is B km/hr then speed in still water = ½(A+B) km/hr
rate of stream =1/2(A-B) km/hr

H.C.F and L.C.M Concept

noreply@blogger.com (Ravi Kumar) — Thu, 04 Aug 2011 13:44:00 +0000

Facts And Formulae:

Highest Common Factor:(H.C.F) or Greatest Common Measure(G.C.M) :
The H.C.F of two or more than two numbers is the greatest number that divides each of them exactly.

There are two methods :

i.Factorization method: Express each one of the given numbers as the product of prime factors. The product of least powers of common prime factors gives HCF.

Example : Find HCF of 26 * 32*5*74 , 22 *35*52 * 76 ,
2*52 *72
Solution: The prime numbers given common numbers are 2,5,7
Therefore HCF is 22 * 5 *72 .

ii.Division Method : Divide the larger number by smaller one. Now divide the divisor by remainder. Repeat the process of dividing preceding number last obtained till zero is obtained as number. The last divisor is HCF.

Least common multiple[LCM] : The least number which is divisible by each one of given numbers is LCM.

There are two methods for this:
i.Factorization method : Resolve each one into product of prime factors. Then LCM is product of highest powers of all factors.

ii.Common division method.

Ratio and Proportions Concept

noreply@blogger.com (Ravi Kumar) — Tue, 02 Aug 2011 09:27:00 +0000

Ratio and Proportions concepts

Ratio and Proportions:

Ratio is denoted by ":"
The form of ratio is a:b. Here a,b are called terms.

1.Ratio:
The ratio of two qualities a and b in the same units, is the fraction a/b and we write it as a:b. In the ratio, a:b, we call ‘a’ as the first term of antecedent and b, the second term consequent.
Ex: The ratio 5:9 represents 5/9 with antecedent=5 ,consequent=9

2.Rule:
The multiplication or division of each term of 9 ratio by the same non-zero number does not affect the ratio.

3.Proportion:
The equality of two ratios is called proportion. If a:b=c:d, we write a:b::c:d and we say that a,b,c and d are in proportion. Here a and b are called extremes, while b and c are called mean terms.
Product of means=product of extremes
Thus, a:b::c:d => (b*c)=(a*d)

4.Fourth proportional:
If a:b::c:d, then d is called the fourth
proportional to a,b and c.

5.Third proportional:
If a:b::b:c, then c is called third
proportional to a and b.

6.Mean proportional:
Mean proportional between a and b is SQRT(a*b).

7.Comparision of Ratios:
We say that (a:b)>(c:d) => (a/b)>(c/d)

8.Compounded ratio:
The compounded ratio of the ratios (a:b),
(c:d),(e:f) is (ace:bdf).

9.Duplicate Ratio:
If (a:b) is (a2: b2 )

Sub-duplicate ratio of (a:b) is (SQRT(a):SQRT(b))

Triplicate ratio of (a:b) is (a3: b3 )

Sub-triplicate ratio of (a:b) is (a1/3: b1/3 ).
If a/b=c/d, then (a+b)/(a-b)=(c+d)/(c-d) (componend o and dividend o)

Pure Or Applied Mathematics: Which Is More Difficult?

noreply@blogger.com (Ravi Kumar) — Wed, 27 Jul 2011 12:09:00 +0000

Pure mathematics is more like art. Pure mathematicians work on building a foundation for a theory. One nice feature about pure mathematics is that it is free from argument. When a mathematician makes a discovery there is no opposition, as in science. And his theory stands the test of time, unlike science where one law is shown to be wrong in special cases. But once a foundation is build (like complex analysis) applied mathematicians take its result and use it to solve important problems.

Pure math is much more difficult. Classes in applied math consist of memorizing the steps to solve problems. However, classes in pure math involve proofs, which implies a good understanding of the subject matter is required. In pure math you need to justify everything you do. Which can sometimes make a simple argument long and complicated. It is easier for someone in pure math to learn applied math rather than someone in applied math to learn pure math.

Pipes and Cisterns Concept

noreply@blogger.com (Ravi Kumar) — Sat, 23 Jul 2011 09:20:00 +0000

1. INLET:A pipe connected with a tank or cistern or a reservoir, that fills it, it is known as Inlet.

OUTLET:A pipe connected with a tank or a cistern or a reservoir, emptying it, is known as Outlet.

2. i) If a pipe can fill a tank in x hours, then : part filled in 1 hour=1/x.

ii)If a pipe can empty a tank in y hours, then : part emptied in 1 hour=1/y.

iii)If a pipe can fill a tank in x hours and another pipe can empty the full tank in y hours( where y>x), then on opening both the pipes, the net part filled in
1 hour=(1/x -1/y).

iv)If a pipe can fill a tank in x hours and another pipe can empty the full tank in y hours( where x>y), then on opening both the pipes, the net part filled in 1 hour=(1/y -1/x).

v) If two pipes A and B can fill a tank in x hours and y hours respectively. If both the pipes are opened simultaneously, part filled by A+B in 1 hour= 1/x +1/y.

Time and Distance Concept

noreply@blogger.com (Ravi Kumar) — Thu, 14 Jul 2011 09:21:00 +0000

I)Speed = Distance/Time

II)Time = Distance/speed

III) Distance = speed*time

IV) 1km/hr = 5/18 m/s

V)1 m/s = 18/5 Km/hr

VI)If the ratio of the speed of A and B is a:b,then the ratio of the time taken by them to cover the same distance is 1/a : 1/b or b:a

VII) suppose a man covers a distance at x kmph and an equal distance at y kmph.then the average speed during the whole journey is (2xy/x+y)kmph

basic formulas

noreply@blogger.com (Ravi Kumar) — Mon, 11 Jul 2011 07:13:00 +0000

->(a+b)²=a²+b²+2ab
->(a-b)²=a²+b²-2ab
->(a+b)²-(a-b)²=4ab
->(a+b)²+(a-b)²=2(a²+b²)
->a²-b²=(a+b)(a-b)
->(a-+b+c)²=a²+b²+c²+2(ab+b c+ca)
->a³+b³=(a+b)(a²+b²-ab)
->a³-b³=(a-b)(a²+b²+ab)
->a³+b³+c³-3a b c=(a+b+c)(a²+b²+c²-ab-b c-ca)
->If a+b+c=0 then a³+b³+c³=3a b c

True Discount Concept

noreply@blogger.com (Ravi Kumar) — Sun, 10 Jul 2011 09:41:00 +0000

General Concept:

Suppose a man has to pay Rs.156 after 4 years and the rate of interest is 14%per annum.
Clearly ,Rs.100 at 14% will amount to Rs156 in 4 years
So,the payment of Rs.100 now wil cear off the debt of Rs156 due 4 years hence
We say that Sum due = Rs156 due 4 years hence Present Worth =Rs100
True Discount=Rs.156-Rs100=Rs56=Sumdue-PW
We define
TrueDiscount= Interest on Present Worth(PW) Amount = PresentWorth+TrueDiscount

Formulae:

Let rate=R%per annum, Time= T years

1.Present worth (PW) = (100*Amount)/(100+(R*T))
= (100* TrueDiscount)/(R*T)

2.TrueDiscount (TD) = (P.W*R*T)/100
= (Amount*R*T)/(100+(R*T))

3.Sum =(SimpeInterest*TrueDiscount)/(SimpleInterest-TrueDiscount)

4.SimpleInterest-TrueDiscount=SimpeInterest on TrueDiscount

5.When the sum is put at CompoundInterest,then

PresentWorth=Amount/(1+(R/100))^T

Why Are Mathematical Concepts Difficult to Understand

noreply@blogger.com (Ravi Kumar) — Thu, 07 Jul 2011 04:39:00 +0000

Mathematical concept means just about anything with a mathematical name. For example, some of the mathematical concepts we learn in high school are: constant, variable, polynomial, factor, factoring, equation, solving an equation, logarithm, sine, cosine, tangent, etc., point, line, triangle, square, and other geometric figures, area, perimeter of a geometric figure, etc., and many others. Among the mathematical concepts we learn in our first years of college mathematics are: set, operation, limit, function, and, specifically, continuous function, derivative, integral, theorem, proof, countable infinity, uncountable infinity, algebra, linear algebra, vector space, group, ring, field, and many others.

Now one thing that makes the understanding of these concepts difficult is that they are defined in terms of other concepts.

Thus, e.g., a vector space is defined in terms of the concepts of vector, set, function, abelian group, field, and others. How does the typical mathematics textbook, and mathematics course, deal with this fact? It attempts to teach the concepts in logical order, i.e., it assumes that, e.g., when you begin your study of vector spaces, you will already know — through having remembered what you learned in previous courses — the meaning of each of the concepts in terms of which a vector space is defined. And, indeed, one of the things that makes mathematics such a frightening subject to many students, is the grandiose manner with which these assumptions are set forth in the list of prerequisites for the course.

Time and Work Concept

noreply@blogger.com (Ravi Kumar) — Tue, 05 Jul 2011 09:23:00 +0000

1.If A can do a piece of work in n days, then A's 1 day work=1/n

2.If A's 1 day's work=1/n, then A can finish the work in n days.

Ex: If A can do a piece of work in 4 days,then A's 1 day's work=1/4.
If A's 1 day’s work=1/5, then A can finish the work in 5 days

3.If A is thrice as good workman as B,then: Ratio of work done by
A and B =3:1. Ratio of time taken by A and B to finish a work=1:3

4.Definition of Variation: The change in two different variables follow some definite rule. It said that the two variables vary directly or inversely.Its notation is X/Y=k, where k is called constant. This variation is called direct variation. XY=k. This variation is called inverse variation.

5.Some Pairs of Variables:

i)Number of workers and their wages. If the number of workers increases, their total wages increase. If the number of days reduced, there will be less work. If the number of days is increased, there will be more work. Therefore, here we have
direct proportion or direct variation.

ii)Number workers and days required to do a certain work is an example of inverse variation. If more men are employed, they will require fewer days and if there are less number of workers, more days are required.

iii)There is an inverse proportion between the daily hours of a work and the days required. If the number of hours is increased, less number of days are required and if the number of hours is reduced, more days are required.

Profit and Loss Concept

noreply@blogger.com (Ravi Kumar) — Fri, 01 Jul 2011 09:26:00 +0000

Cost Price:
The price at which an article is purchased, is called its cost price,abbreviated as C.P.

Selling Price:
The price at which an article is sold, is called its selling price,abbreviated as S.P.

Profit or Gain:
If S.P. Is greater than C.P. The seller is said to have a profit or gain.

Loss:
if S.P. Is less than C.P., the seller is said to have incurred a loss.

Formulae:

1.Gain=(S.P-C.P)
2.Loss=(C.P-S.P)
3.Loss or Gain is always reckoned on C.P.
4.Gain%=(gain*100)/C.P
5.Loss%=(loss*100)/C.P
6.S.P=[(100+gain%)/100]*C.P
7.S.P=[(100-loss%)/100]*C.P
8.C.P=(100*S.P)/(100+gain%)
9.C.P=(100*S.P)/(100-loss%)
10.If an article is sold at a gain of say,35%,then S.P=135% of C.P.
11.If an article is sold at a loss of say,35%,then S.P=65% of C.P.
12.When a person sells two similar items, one at a gain of say, x%, and the other at a loss of x%,then the seller always incurs a loss given by Loss%=[common loss and gain %/10]2=(x/10)2
13.If a trader professes to sell his goods at cost price,but uses
false weight,then Gain%=[(error/(true value-error))*100]%
14.Net selling price=Marked price-Discount

Mathematics Is Easy Once You Have Learned It

noreply@blogger.com (Ravi Kumar) — Sun, 26 Jun 2011 07:03:00 +0000

The most difficult mathematics is that which you do not know.

A surprising amount of mathematics is actually easy once you've learned it. Of course, once you learn the easy stuff, then you have to start tacking the deep stuff, and that gets harder.

One teacher I had, was introducing a new concept, and we did an example in class. (and this was a class for good mathematicians -- not your average students) There was a lot of blank stares, and not everybody seemed to follow all the way through.

The very next thing he asked was for us to differentiate the function x² with respect to x. Of course, everybody could do that very easily.

His response? "The reason you can do differentiation, but not the other thing, is that you've differentiated things hundreds of times, but you haven't done this other thing very much yet."

Percentages Concept

noreply@blogger.com (Ravi Kumar) — Thu, 23 Jun 2011 09:28:00 +0000

Percentage means "expressing one quantity as per cent".

1.To convert a common fraction into per cent, we multiply the fraction with 100. And put % symbol to the result.

2.To convert a percent into fraction we must remove % symbol., divide it with 100 and simplify the product.

3.If the population of a town(or the length of a tree) is P and annual increase is r% then:
*population after n years = P[1+(r/100)]^n
*population n years ago = P/(1+r/100)^n

4.If the population of a town(or the length of a tree) is P and annual decrease is r% then:
*population after n years = P[1-(r/100)]^n
*population n years ago = P/(1-r/100)^n

Chain Rule Concept

noreply@blogger.com (Ravi Kumar) — Thu, 16 Jun 2011 06:49:00 +0000

Important Facts:

Direct Proportion: Two Quantities are said to be directly
proportional, if on the increase (or decrease) of the one, the
other increases(or decreases) to the same extent.

Ex:(i) Cost is directly proportional to the number of articles.
(More articles, More cost).

(ii) Work done is directly proportional to the number of men
working on it. (More men, more work).

Indirect Proportion: Two Quantities are said to be
indirectly proportional,if on the increase of the one , the other
decreases to the same extent and vice-versa.

Ex:(i) The time taken by a car covering a certain distance is
inversely proportional to the speed of the car.(More speed,
less is the time taken to cover the distance).

(ii) Time taken to finish a work is inversely proportional to
the number of persons working at it.
(More persons, less is the time taken to finish a job).

Note: In solving Questions by chain rule, we compare every
item with the term to be found out.

Races and Games Concept

noreply@blogger.com (Ravi Kumar) — Tue, 14 Jun 2011 07:05:00 +0000

Important Facts and Formulae:

Races:
A contest of speed in running ,riding,driving,sailing or rowing is called a Race

Race Course:
The ground or path on which contests are made is called a race course

Starting Point:
The point from which a race begins is called starting point.

Winning point or goal:
The point set to bound a race is called a winning point.

Dead Heat Race:
If all the persons contesting a race reach the goal exactly at the same time,then the race is called a dead heat race.

Start:
Suppose A and B are two contestants in a race .If before the start of the race,A is at the satrtint point and B is ahead of A by 12 metres. Then we say that "A gives B a start 12 metres.

->To cover a race of 100metres in this case,A will have to cover 100m while B will have to cover 88m=(100-12)

->In a100m race 'A can give B 12m' or 'A can give B a start of 12m' or 'A beats B by 12m'means that while A runs 100m B runs 88m.

Games:
A game of 100m,means that the person among the contestants who scores 100 points first is the winner.

If A scores 100 points while B scores only 80 points then we say that 'A can give B 20 points'.

Bankers Discount Concept

noreply@blogger.com (Ravi Kumar) — Fri, 10 Jun 2011 07:11:00 +0000

Formulae:

i. Suppose a merchant A buys goods worth Rs.10000 from another
merchant B at a credit of say 5 months

ii.Then,B prepares a bill , called the bill of exchange

iii. A signs this bill & allows B to withdraw the amount from his
bank account after exactly 5 months,the date exactly after
5 months is called Nominally due date

iv. Three days (grace days) are added to it get a date known as
legally due date

v.Suppose B wants to have money before legally due date then he
can have the money from banker or a broker who deducts S.I on the
face value (i.e., 10000) for the period from the date on which
the bill was discounted (i.e paied by the banker) & the legally
due date this amount is known as Bankers Discount

vi.Thus , B.D is the S.I on the face for the period from the date
on which the bill was discounted and the legally due date

vii.Bankers Gain (B.G) = (B.D) â€“ (T.D) for the unexpired time

Note:
When the date of the bill is not given,grace days are not to be added

Formulae:

(1)B.D = S.I on bill for unexpired time
(2)B.G = (B.D) â€“ (T.D) = S.I on T.D = (T.D)^2 /P.W
(3)T.D = sqrt(P.W * B.G)
(4)B.D = (Amount * Rate * Time)/100
(5)T.D = (Amount * Rate * Time)/(100+(Rate * time)
(6)Amount = (B.D * T.D)/(B.D â€“ T.D)
(7)T.D = (B.G * 100)/(Rate * Time)

Boats and Streams

noreply@blogger.com (Ravi Kumar) — Sun, 22 May 2011 09:28:00 +0000

Boats and Streams concept:

Boats and Streams:

1)In water, the direction along the stream is called down stream.

2)Direction against the stream is called upstream.

3)The speed of boat in still water is U km/hr and the speed of
tream is V km/hr then

speed down stream =U + V km/hr
speed up stream = U – V km/hr

Formulae:

If the speed down stream is A km/hr and the speed up stream is
B km/hr then speed in still water = ½(A+B) km/hr
rate of stream =1/2(A-B) km/hr

Averages

noreply@blogger.com (Ravi Kumar) — Fri, 20 May 2011 09:25:00 +0000

Averages concepts

Averages:

*Average = (Sum of quantities)/(Number of quantities)

*Suppose a man covers a certain distance at x kmph
and an equal distance at y kmph ,then the average speed
during the whole journey is (2xy/x+y) kmph.

*To find the average of given numbers(72,59,18,101,7) just add all these numbers and divide the sum with number of given numbers.

*If a man covers a journey from A to B by car at an average speed of X kmph. He returns back with a scooter with Y kmph then his average speed during the whole journey is 2XY/X+Y kmph.