Question

$18, P = $200, r = ?, t = 1.5 years. Find the annual interest rate.

I = $60, P = $750, r = 4%, t = ?. Find the amount of time. (sorry I added this one as well the other time I asked this no responded but you don't have to answer this if you want)

Answer 1

Question 1)

Given

Interest I = $18

Principle P = $200

t = 1.5 years

To determine

Interest rate r = ?

Using the formula

`P = Irt`

`r=(I)/(Pt)`

susbtituting I = 18, t = 1.5 and P = 200

`r=(18)/(\left(200* 1.5\right))`

`r = 0.06`

or

r = 6% ∵ 0.06 × 100 = 6%

Therefore, we conclude that the interest rate required to accumulate simple interest of $18.00 from a principal of $200 over 1.5 years is 6% per year.

Question 2)

Given

Interest I = $60

Principle P = $750

Interest rate = 4% = 0.04

To determine

Time period t = ?

Using the formula to calculate the time period

`P = Irt`

`t\:=\:(P)/(Ir)`

`t=(60)/(\left(750* 0.04\right))`

`t = 2` years

Therefore, the time required to accumulate simple interest of $ 60.00

from a principal of $ 750 at an interest rate of 4% per year is 2 years.