Question

The ratio x : y is equal to 2 : 5, and y is 80% of z. Write an equation to represent the proportional relationship between x and z.

Answer 1

• x : z = 8 : 25

Explanation:

Given

• x : y = 2 : 5, y is 80% of z

Rearranging the ratios:

• x/y = 2/5 ⇒ x/y = 0.4 ⇒ y = x/0.4 ⇒ y = 2.5x
• y is 80% of z ⇒ y = 0.8z

Comparing the values of y:

• 2.5x = 0.8z
• x/z = 0.8/2.5
• x/z = 0.32
• x/z = 32/100
• x/z = 8/25
• x : z = 8 : 25