Question

P varies directly as q. When q = 31.2, p = 20.8. Find p when q = 15.3.

a.10.2
b.22.95
c.42.4
i got B ...?

Answer 1

we know that

A relationship between two variables, x, and y, represent a direct variation if it can be expressed in the form
`y/x=k` or
`y=kx`

In this problem we have

`p=20.8\\q=31.2`

Find the value of k

`k=q/p`

Substitute the values

`k=31.2/20.8`

`k=1.5`

The linear equation is

`q=1.5p`

For
`q=15.3`

Find the value of p

Substitute in the linear equation and solve for p

`15.3=1.5p`

`p=15.3/1.5=10.2`

therefore

the answer is the option a

`10.2`