Question

13.two quantities ,x and y, vary directly, if x=5 and y=20, find y when x=45.

14.two quantities ,x and y, vary directly, if x=8 and y=48, find y when x=32.

Answer 1

Answer: 13. 180, 14. 192

Explanation:

13.

What is the relationship of 5 and 20?

4x5 is 20.

That means y is 4 times more than x.

So, if you apply this to x= 45, what is y?

45x4 =180

This can be used as a ratio

5:20

45: ?

To get 5 to 45, multiply by 9

That means you have to equal out the equation by multiply 20 by 9, = 180.

14.

8: 48

32: ?

8x4 is 32

48x4=192

y= 192