What was the percentage change in the simple average profit per car

Question

What was the percentage change in the simple average profit per car sold by dealer X from 2000 to 2009?

(1) The total profit from car sales at dealer X increased by 70% from 2000 to 2009
(2) The total number of cars increased from 1253 in 2000 to 1687 in 2009

kannu44 · Accepted Answer

Let profit in year 2000 be X then average profit = X/1253
Profit in year 2009 1.7 X (From statement 1) -> Average profit 1.7X/1687

With both above we can calculate percentage change in average profit

Hoozan · Answer

EducationAisle  if the overall profit increased by 70% then can't we say that the avg profit also increased by 70%?

Could you help solve this

EducationAisle · Answer

Thing is that the question is asking for average profit "per car sold".

Since the "number of cars sold" were obviously different in 2000 and 2009, we need to take "number of cars sold" into consideration.

A simple example:
i) In 2000:
number of cars sold = x
Total profit = $100
=> Average profit "per car sold" = 100/x

ii) In 2009:
Say, number of cars sold = y
Total profit = $170
=> Average profit "per car sold" = 170/y

So, number of cars sold ("x" and "y" respectively) also matter.

anirchat · Answer

Let average profit in 2000 and 2009 be p1 and p2.
Let number of cars sold in 2000 and 2009 be n1 and n2.

To evaluate : (p2-p1)/p1 * 100 ----- (i)

Option A) n2p2 = 1.7*n1p1 -> Not sufficient to evaluate (i).
Option B) n1 = 1253, n2 = 1687 -> Not sufficient to evaluate (i).

But using both, we can evaluate (i). So,  C  is the right answer.

GGGMAT2 · Answer

Here, statement 2 says, the number of cars increased from 1253 in 2000 to 1687 in 2009. But it doesnt say if this is an increase in inventory or an increase in the cars sold. We are assuming that this increase is the increase in number of cars sold. Is this a fair assumption to make?

@EducationAisle [b]bb Bunuel @Bismuth83 [/b]

@ EducationAisle    bb   Bunuel   @Bismuth83

Bunuel · Answer

I believe the word "sold" is simply missing from the sentence.

Nipunh · Answer

we are asked to find the percentage change in **average profit per car sold** by dealer x from 2000 to 2009

average profit per car = total profit ÷ total number of cars
so percentage change in average = \  × 100
which means we need both total profit and number of cars in 2000 and 2009 to compute average for both years

statement 1 gives total profit increased by 70%
but gives no info about number of cars in either year
so we can't compute the average for either year
not sufficient

statement 2 gives car numbers in both years
but gives no info about profit in either year
again, can’t calculate average profit
not sufficient

together:
statement 1 gives profit increased by 70%
let profit in 2000 be p → then in 2009 it’s 1.7p
statement 2 gives number of cars:
2000 = 1253
2009 = 1687

now we compute average in both years:
average 2000 = p / 1253
average 2009 = 1.7p / 1687
percentage change = \  × 100
p cancels out
we can compute exact % change

so together, sufficient

answer is c

What was the percentage change in the simple average profit per car

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What was the percentage change in the simple average profit per car

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