On your ninth birthday, you received $300 which

Ответ:

parisowl7900

01.01.2022

30 years

Step-by-step explanation:

On your ninth birthday, you received $300 which you invested at 4.5 percent interest, compounded annually.

Principal amount is $300

rate of interest is 4.5%

your investment is now worth $756. So amount after t year is $756

We use compound interest formula

A=P(1+r)^t

A is the final amount

P is principal amount

r is the rate of interest 0.045

t is the number of years

Plug in the values in the formula

756=300(1+0.045)^t

Divide both sides by 300

$\frac{756}{300}=1. 045^t$

Take ln on both sides

$ln\frac{756}{300}=t ln(1. 045)$

Divide both sides by ln(0.045)

t= 20.99= 21 years

9 years + 21 years = 30 years

She is 30 years old now

0,0(0 оценок)