Question

Kimberly received $75 in interest on $1500 in her bank account. If the interest varies directly with the amount deposited, what equation represents this situation?

Answer 1

`I=(1)/(20)A`

Explanation:

Let
`I` represent interest and
`A` represent the amount.

Then we were given that: "the interest varies directly with the amount deposited".

This is written symbolically as:

`I\propto A`

When we introduce the constant of proportionality; we get:

`I=kA`

From the question, when I=75, A=1500.

We substitute and solve for k.

`75=1500k`

`\implies k=(75)/(1500)\\ \impies k=(1)/(20)`

Hence the required equation is
`I=(A)/(20)`