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The value of y varies directly with x. When x = 5, y = 7.5. What is the value of y when x = 15?

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Answer:

22.5

Explanation:

SINCE Y VARIES DIRECTLY WITH X, WE USE THE FORMULA

y=kx; k representing the variable change, y= 7.5, x=5

> y=kx

>7.5= k(5) > 7.5= 5k

>k= 7.5/5 (divide to get the k)

k= 1.5

NOW REPLACE THE NEW VALUES OF X AND K AS THE VARIABLE CHANGE, TO FIND THE VALUE OF Y

>y=kx ; k=1.5 and x=15 y=?

>y= (1.5)(15)

>y=22.5

the value of y is 22.5 when x is 15

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