averages

answer is (a) - option 1 is enough.

if equal no of shirts n sweaters were sold, the avg price will be $20.

Assume the store sold n shirts and n sweaters
$avg price = (15n +25 n)/2n
= 40n/2n
= 20

As the given avg price is greater than $20, the store sold more of the higher priced item ie sweaters.

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Option B -
is not sufficient as it means
420=15h+25w
which has multiple solutions.

Let the number of shirts sold = x

sweaters sold = y

therefore,

average = (15x + 25y)/(x+y) = 21

or 15x + 25y = 21x + 21y

or 6x = 4y

3x = 2y

So, more sweaters were sold than shirts

we can check this by plugging in for x

lets say x = 2
therefore, y from the above equation is 3

IMO A

statement 2 is insuficient

uttara wrote:
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Option B -
is not sufficient as it means
420=15h+25w
which has multiple solutions.

IMO D.

I can think of only one solution for the eq, 420=15h+25w

15 x 8 + 25 x 12 = 420

Smohsin,
The question is "Did the store sell more sweaters than shirts" We can tell this if we can find the ratio of shirts to sweaters which we can from statement I

If the question had asked how many sweaters then we need both stataments to find x or y.


I think the key is to recognioze whast being asked and the reason whcy I am saying this is because I have made mistakes in DS porblems by overlooking whats asked.

Hope this helps.

Smohsin,
The question is "Did the store sell more sweaters than shirts" We can tell this if we can find the ratio of shirts to sweaters which we can from statement I

If the question had asked how many sweaters then we need both stataments to find x or y.


I think the key is to recognioze whast being asked and the reason whcy I am saying this is because I have made mistakes in DS porblems by overlooking whats asked.

Hope this helps.

callmemo wrote:IMO D.

I can think of only one solution for the eq, 420=15h+25w

15 x 8 + 25 x 12 = 420

15*3 + 25*15

ah! thanks. Is there an easy way to enumerate all combinations? OR is it simply by trail and error?