The task is to generate the correct answer for a given math problem.
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Question: Problem: if 4 xz + yw = 10 and xw + yz = 20 , what is the value of the expression ( 2 x + y ) ( 2 z + w ) ?

Answer: 50 .


Question: Problem: the cost of the paint is rs . 50 per kg . if 1 kg of paint covers 20 sq . ft , how much will it cost to paint outside of a cube having 20 feet each side

Answer: rs . 6000


Question: Problem: a batsman in his 17 th innings makes a score of 85 and their by increasing his average by 3 . what is his average after the 17 thinnings ?

Answer:
37