The task is to generate the correct answer for a given math problem.

Problem: if 4 xz + yw = 10 and xw + yz = 20 , what is the value of the expression ( 2 x + y ) ( 2 z + w ) ?
50 .

Problem: the ratio of a to b is 4 to 5 , where a and b are positive . if x equals a increased by 25 percent of a , and m equals b decreased by 60 percent of b , what is the value of m / x ?
2 / 5

Problem: a , b , c , d , e , f , g , h sitting in a row what is the probability that a , b , c sitting together ?

3 / 28