Question

fill in the blanks.
principal: $450
rate: ?
time: 3 years
interest earned: 67.50
new balance: ?

Answer 1

Answer:

r=5%

New balance=$ 517.5

Step-by-step explanation:

We use the simple interest formula:

I=prt.

to determine the rate per annum of a principal of $450 that is invested for 3 years and earned an interest of $ 67.5

We substitute to get:

67.5=450×r×3

$r = \frac{67.5}{3 \times 450}$

We simplify to get:

$r = 0.05$

The rate of interest is 5%

The new balance is

Principal + Interest.

$= 450 + 67.5$

$= 517.5$

The new balance $517.5