Question

If $3,500.00 is invested at 5% simple interest, how much additional money needs to be invested at 7%simple interest so the total interest per year is $553.00.You would need to invest sat 7% simple interest (NO COMMAS).

Answer 1

Answer:

Explanations:

The amount invested is the principal, P

P = $3500

Rate, R = 5%

Time, T = 1 year

The formula for Simple Interest is given as:

`I\text{ = }(PRT)/(100)`

`\begin{gathered} I\text{ = }(3500*5*1)/(100) \\ I\text{ = }175 \end{gathered}`

The 5% Interest on $3500 = $175

The total interest = $553

Interest at 7% rate = $553 - $175

Interest at 7% rate = $378

The amount that will be invested at 7% interest rate will then be calculated using the formula

`\begin{gathered} I\text{ = }(PRT)/(100) \\ 378\text{ = }(P*7*1)/(100) \\ 378(100)\text{ = 7P} \\ 37800\text{ = 7P} \\ P\text{ = }(37800)/(7) \\ P\text{ = }5400 \end{gathered}`

You will need to invest $5400 at 7% simple interest