On your ninth birthday, you received $300 which you invested at 4.5 percent interest, compounded annually. your investment is now worth $756. how old are you today?

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 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

Divide both sides by 300

Take ln on both sides

Divide both sides by ln(0.045)

t= 20.99= 21 years

9 years + 21 years = 30 years

She is 30 years old now

$4034.40

the perimeter of the field is the sum of the lengths of the four sides:

47 yd + 158 yd + 47 yd + 158 yd = 410 yd

the cost of 3 ft (1 yd) of fence is 3×$3.28 = $9.84.

so the cost of jake's wood perimeter fance is

(410 yd) × ($9.84 /yd) = $4034.40