In a grocery store, the average sale for month X was A

Question

In a grocery store, the average sale for month X was A dollars. Was the average sale for month Y at least 20 percent higher than that for month X?

(1) For month X, total revenue from sales was $ 35,000

(2) For month Y, total revenue fro sales was $ 60,000

kapslock · Answer

This looks like C.

Anyone wants to try a variation?

Total revenues in Y = $40,000.

maaverick · Answer

If "the average sale for month X" implies, average daily sales for month X, I would go with (E).

Month X could have any of 31, 30, 28 or 29 days.

Since the avegare daily sales = A, the total sales for Month X could be any of: 31X, 30X, 28X or 29X

Now, month Y could have any of 31, 30, 28 or 29 days in all.

Clearly, statements (1) and (2) are insufficient if treated separately, let us just examine case (C) here:

For month X, total revenue from sales was $ 35,000 - (1)
AND
For month Y, total revenue fro sales was $ 60,000 - (2)

(1) implies, the average daily sales for Month X could be
- $35000/31 or
- $35000/30 or
- $35000/29 or
- $35000/28

(2) average daily sales for Month Y could be
- $60000/31 or
- $60000/30 or
- $60000/29 or
- $60000/28

Hence, both combined, insufficient.

Is my approach fine or am I just being paranoid?

banerjeea_98 · Answer

EDITED:

"C" ....we don't know what type of month we are talking about but for any combination of avg X/28,X/29,X/30,X/31 ( min avg will be when X/31 and max for X/28) same for Y.....we can calculate that in all cases avg (u can only calcualte min and max avg) of Y is always > than 20% X....so suff....I guess if Y was 40,000 then it will be E, altho I haven't calculated it.

vprabhala · Answer

hmmm could be E dunno about the number of days..

gmat2me2 · Answer

Questions that seem straight would have tough solutions

I would go for E

scorer · Answer

'C'

For all combinations (month --> 28,29,30,31) month Y avg is 20% greater than month X avg

lastochka · Answer

I selected E
you need to know the number of transactions for each month to compute the average sale value. 

What's the OA?

Folaa3 · Answer

I think the ans is C. 
If the question stem didnâ€™t ask for â€œat leastâ€

swath20 · Answer

Dont have the OE but the OA is E

HongHu · Answer

Explanation for choose E might be because "average sales" is undefined in the question. You guys added the word "daily" to make it clear, but is it the intend of the question?

HongHu · Answer

Good thinking but will this not lead to answer E, for if you calculate them out you'll see the answer is unique and C would be your answer.

In a grocery store, the average sale for month X was A

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