shreygupta3192 wrote:

A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold?

(A) 10

(B) 20

(C) 30

(D) 32

(E) 34

hey can any1 plz tell me ..

if ques says that no 20 ounce bottles are sold..

then y r we considering "20*12" while calculating the new ratio..

wats the meaning and the use of that line above.."

no 20 ounce bottles are sold"

y can`t we directly put 0 bottles for 20 ounces..

y can`t we go directly for ..

25=(20(0)+40(x))/x..

confused..

No. The question asks about the average weight of bottles which are not sold.

A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold? (A) 10

(B) 20

(C) 30

(D) 32

(E) 34

The current average of 20 (35 -

15) and 40-ounce (40 -

5) bottles is 35, thus there must be 3 times as many 40-ounce bottles as 20-ounce bottles. Since there are total of 48 bottles, then there must be 12 20-ounce bottles and 36 40-ounce bottles.

Now, we need to sell ONLY 40-ounce bottles so that the average to become 25. Same way, 25 is 5 away from 20 and 15 away from 40, so after selling some number of 40-ounce bottles, there must be 3 times as many 20-ounce bottles as 40-ounce bottles. So, there must be 12 20-ounce bottles and 12/3 = 4 40-ounce bottles.

Therefore, 36 - 4 = 32 40-ounce bottles must be sold.

Answer: D.

Hope it's clear.

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