Question

How much money will you need to deposit to earn $75 in simple interest in 6 months if your banks pays 5% annually?

Answer 1

Do you know how to start it?

Answer 2

They gave me the formulas but I'm not sure which one I have to use.

Answer 3

The amount of simple interest can be found from:
\[\large I=P \times r \times t\ ......(1)\]
where I is the amount of interest after t years and r is the annual interest rate expressed as a decimal.
The find step you need to make is to rearrange equation (1) to find P in terms of I, r and t. This is done by dividing both sides of equation (1) by (r * t).