A vendor buys 10 t-shirts at an average price of $14 per t-shirt. He t

Question

A vendor buys 10 t-shirts at an average price of $14 per t-shirt. He then buys 15 more t-shirts at an average price of $11 per t-shirt. What is the average price per t-shirt that the vendor paid for these purchases?

A. $12.20
B. $12.50
C. $12.55
D. $12.70
E. $13.00

Kudos for a correct solution.

A. $12.20
B. $12.50
C. $12.55
D. $12.70
E. $13.00

Kudos for a correct  solution .

shelrod007 · Answer

Money paid for 10 T shirts , each costing $ 14 : 14 * 10 = 140 ------ Eq 1

Money paid for 15 T shirts , each costing $ 11 : 15 * 11 = 165 ------ Eq 2

Total number of T shirts purchased = 10 + 15 = 25

Average price paid per T shirt = Eq 1 + Eq 2 / Total number of T shirts

= ( 165+ 140 ) / 25 
 = 305 / 25 
 = 12.5 $

Answer is B

eddyki · Answer

Its A.

300/25 -> 12
5/25 -> 1/5 -> 0,2 
=12,2

I calculated this one faster just by doing this:

10$ is the base:
-> 10 shirts for 14-10=4 -> 40$
-> 15 shirts for 11-10=1 -> 15$
so 25 shirts for 55 -> 55/25 -> 2,2

so the number has to end with X2,2 -> A

PareshGmat · Answer

Answer = A. $12.20

Average  = \frac{10*14 + 15*11}{10+15} = \frac{305}{25} = 12.2

pate13 · Answer

11 ----- 14.

14 - 11 = 3. The ratio equation of shirts bought was 2x + 3x = 5x. Divide 3 (the difference in price) by 5 (the total of the ratio equation) to get .6, then multiply by 2 (from the ratio equation) to get 1.2. The answer will be closer to $11 than to $14 since more $11 shirts were bought. 11 + 1.2 = 12.2.

Answer is A.

KarishmaB · Answer

You need to find the average price but the options are such that you actually don't even need to calculate it. 
Mid way between $11 and $14 is $12.50. Since more t-shirts were bought at $11, the weighted average would be closer to $11 than to $14. Hence, the only option that will work will need to be less than $12.50. So, only (A) $12.20 works

Answer (A)

chetan2u · Answer

hi shelrod,
be careful with the calculations..
after doing everything correctly, you have wrongly deduced 305/25 to be 12.5 .. it will be 12.2
ans A

Bunuel · Answer

VERITAS PREP OFFICIAL SOLUTION

Correct Answer: A

Explanation: The relevant formula for this problem is Average = (Sum)/(Number of Terms). Another way to look at the formula is Sum = Average x Number of Terms. For the first purchase, the vendor's sum (total cost) was $140, since 14 x 10 = 140. For the second purchase, the vendor's cost was $165, since 11 x 15 = 165. The grand sum is then $140 + $165, which equals $305. The total number of shirts purchased was 25, so to get the average price per shirt, we divide 305 by 25, which equals $12.20. As a result, the correct answer is A.

NOTE: A relative understanding of weighted average offers a shortcut to this problem. Because the true average of 11 and 14 is 12.5, but the vendor sells more shirts at the lower price than at the higher price, the weighted average must be less than $12.50; only answer choice A is a possibility.

law258 · Answer

10($14/shirt)+15($11/shirt) 
---------------------------- = x
 25

x = $12.2

Abhishek009 · Answer

\frac{( 10*14 ) + ( 15*11 )}{( 10 + 15 )}  =  \frac{(140 + 165)}{25}  =  12.20 
  
Hence answer will be (A) 12.20

A vendor buys 10 t-shirts at an average price of $14 per t-shirt. He t

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A vendor buys 10 t-shirts at an average price of $14 per t-shirt. He t

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