John invested $30000 in the bank for 4 years. At the end of the period, he had
$42520. Calculate
a. the interest earned
b. the rate per annum at which simple interest was earned to 1 decimal place.

Respuesta :

Answer:

Rate = 10.4%

Step-by-step explanation:

Given :

P = $30000

A = $42520

Interest earned = 42520 - 30000 = $12520

Time = 4years

Find R

     [tex]Interest = \frac{PRT}{100}[/tex]

        [tex]12520 = \frac{30000 \times R \times 4}{100}\\\\12520 = 300 \times 4 \times R\\\\12520 = 1200 \times R\\\\R = \frac{12520}{1200}\\\\R = 10.43 \%[/tex]

Round to 1 decimal place, Rate = 10.4%