Last year Bakery A had total sales of cookies in December that was 4 times the average (arithmetic mean) of the monthly cookie sales totals for January through June and 3 times the average total cookie sales for July through November. The cookie sales total for December was what fraction of the total cookie sales for the year?
(A) 3/14
(B) 6/25
(C) 1/4
(D) 2/3
(E) 12/19
simple average
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Agree with, Cris! It should be - 6/25 i.e. B.
Dec : Cookies sold = 12x (Say)
Jan - Jun: Cookies sold = avg cookies sold * no of months = 3x * 6 = 18x
Jul-Nov: Cookies sold = avg cookies sold * no of months = 4x * 5 = 20x
So fraction = 12x/(12x + 18x + 20x) = 6/25
Magical Cook, what's the OA?
Dec : Cookies sold = 12x (Say)
Jan - Jun: Cookies sold = avg cookies sold * no of months = 3x * 6 = 18x
Jul-Nov: Cookies sold = avg cookies sold * no of months = 4x * 5 = 20x
So fraction = 12x/(12x + 18x + 20x) = 6/25
Magical Cook, what's the OA?
Correct me If I am wrong
Regards,
Amitava
Regards,
Amitava
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Correct!camitava wrote:Agree with, Cris! It should be - 6/25 i.e. B.
Dec : Cookies sold = 12x (Say)
Jan - Jun: Cookies sold = avg cookies sold * no of months = 3x * 6 = 18x
Jul-Nov: Cookies sold = avg cookies sold * no of months = 4x * 5 = 20x
So fraction = 12x/(12x + 18x + 20x) = 6/25
Magical Cook, what's the OA?
We can make life even a bit easier by forgetting about the "x".
Let's pick 12 for December cookie sales (since that's the lowest common multiple of 3 and 4, the other numbers involved).
In that case, each of Jan-June will average 3 cookies and each of July-Nov will average 4 cookies.
So, we have 6*3 + 5*4 + 12 = 18+20+12 = 50 total cookies
December is 12/50 or 6/25 of the whole year.
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Hi stuart,
Jan - Jun: Cookies sold = avg cookies sold * no of months = 3 * 6 = 18 i was thinking 4*6 as mentioned in the question
Jul-Nov: Cookies sold = avg cookies sold * no of months = 4* 5 = 20 i was thinking 5*3 as mentioned in the question
can you please explain the answer.
Thanks,
Sibbineni
Jan - Jun: Cookies sold = avg cookies sold * no of months = 3 * 6 = 18 i was thinking 4*6 as mentioned in the question
Jul-Nov: Cookies sold = avg cookies sold * no of months = 4* 5 = 20 i was thinking 5*3 as mentioned in the question
can you please explain the answer.
Thanks,
Sibbineni
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sibbineni, why it will be 4 * 6 and 3 * 5 for Jan - Jun & Jul-Nov respectively? The Qs is saying -sibbineni wrote:Hi stuart,
Jan - Jun: Cookies sold = avg cookies sold * no of months = 3 * 6 = 18 i was thinking 4*6 as mentioned in the question
Jul-Nov: Cookies sold = avg cookies sold * no of months = 4* 5 = 20 i was thinking 5*3 as mentioned in the question
can you please explain the answer.
Thanks,
Sibbineni
So if in december, no of cookies = 12xtotal sales of cookies in December that was 4 times the average (arithmetic mean) of the monthly cookie sales totals for January through June and 3 times the average total cookie sales for July through November
so jan-Jun: 4k = 12x -> k = 3x -> so avg is 3x or 3 (according to Stuart!)
Got me?
Correct me If I am wrong
Regards,
Amitava
Regards,
Amitava
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According to the question stem, December was 4 times the average for Jan-June. So, if we let December = 12, we get:sibbineni wrote:Hi stuart,
Jan - Jun: Cookies sold = avg cookies sold * no of months = 3 * 6 = 18 i was thinking 4*6 as mentioned in the question
Jul-Nov: Cookies sold = avg cookies sold * no of months = 4* 5 = 20 i was thinking 5*3 as mentioned in the question
can you please explain the answer.
Thanks,
Sibbineni
12 = 4 * Jan-June
Jan-June = 12/4 = 3
Similarly, for July-Nov, if December is 3 times the average for July-Nov, we get:
12 = 3 * July-Nov
July-Nov = 12/3 = 4
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
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