Question

The sum of the numbers x, y, and z is 50. The ratio of x to y is 1 : 4, and the ratio of y to z is 4 : 5. What is the value of y?

A. 4
B. 8
C. 10
D. 20

Answer 1

D. 20

Explanation:

x:y:z

1:4:5

1+4+5=10

50÷10=5

1=5

4=?

4=4×5

=20

Answer 2

x：y：z

1：4

4：5

-------------

1：4：5

-------------

let a:b:c＝k:4k:5k

k+4k+5k=50

10k=50

k=5

y=4(5)

=20(D)