Question

HELP FOR A MEDAL!! ms.Campbell invested $7200 for 2 1/2 years. If she earned $756, at what rate(R) did she invest her money?

Answer 1

money earned = (investment)*(1+rate/100)^time

Answer 2

plug in your numbers and solve for r

Answer 3

I did ....7200=(756) (?) (2 1/2) I=PRT

Answer 4

I multiplied (756) * (2 1/2) and got 1890 and then divide 7200/ 1890 and got 3.8095238 it's wrong :(

Answer 5

756 = (7200)(1+rate/100)^(2.5)

Answer 6

(756/7200) = (1+rate/100)^2.5

Answer 7

(756/7200)^(1/2.5) = 1 + rate/100

Answer 8

(756/7200)^(1/2.5) - 1 = rate/100

Answer 9

I got 0.042

Answer 10

oh, whoops, small mistake on my part

money earned = 7200+756

([7200+756]/7200)^(1/2.5) - 1 = rate/100
solve for rate

Answer 11

Hmmm would it be cross multiply 1.105 1/2.5 ?? :)