Question

X varies directly as y, and x = 153 when y = 9. Find x when y = 13.

A: 106

B: 157

C: 221

Answer 1

c. 221. 13 divided by 9 times 153

Answer 2

The value of x is 221 when k = 17 and y = 13.

Therefore the Option (C) is correct .

Explanation:

As given

x varies directly as y.

`x\propto y`

x = ky

Where k is the constant of proportionality.

As given

x = 153 when y = 9

Put in the above

153 = 9k

`k = (153)/(9)`

k = 17

Now Find out the value of x when k = 17 and y = 13.

x = ky

x = 17 × 13

x = 221

The value of x is 221 when k = 17 and y = 13.

Therefore the Option (C) is correct .