Question

Simple interest I in dollars is calculated using the formula I=​prt, where p represents the​ principal, or amount in dollars that is invested or​ borrowed; r represents the annual interest​ rate, expressed as a​ decimal; and t represents​ time, in years. Find the value of the variable​ t, using the simple interest formula.

I=$540, p=$4800, r=4.5

Write the interest rate r as a decimal.

r = ?

Answer 1

and we do this one the same way as the other.

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Answer 2

`t=2.5`

Explanation:

We have been given the formula to simple interest. We are asked to find the variable t using the given formula and given values.

Simple interest formula:
`I=Prt`, where,

`I` = Amount of interest after t years,

P = Principal amount,

r = Annual interest rate in decimal form,

t = Time in years.

Given:
`I=\$540`,
`P=\$4800`,
`r=4.5`

Let us convert our given interest rate in decimal form.

`r=4.5\%=(4.5)/(100)=0.045`

Upon substituting our given values in simple interest formula, we will get:

`\$540=\$4800\cdot 0.045t`

`\$540=\$216t`

`(\$540)/(\$216)=(\$216t)/(\$216)`

`2.5=t`

Therefore, the value of t is 2.5 years.