Thor invests $3000 in an account, with interest compounded continuously. If his investment doubles in value after 7.2 years, what interest rate is he earning? [Use the formla A = Pert and round answer to the nearest tenth.]

A) 8.5%

B) 9.6%

C) 12.3%

D) 14.0%

Question

Dante Ford

Mathematics

27 January, 18:34

Thor invests $3000 in an account, with interest compounded continuously. If his investment doubles in value after 7.2 years, what interest rate is he earning? [Use the formla A = Pert and round answer to the nearest tenth.]

A) 8.5%

B) 9.6%

C) 12.3%

D) 14.0%

+2

Answers (1)

Know the Answer?

Darrell Gillespie · Answer 1

B. 9.6 %.

Step-by-step explanation:

A = P e^rt

His investment doubles so it comes to 3000 * 2 = $6000.

Substituting in the formula>

6000 = 3000e^7.2r ehere r is the interest rate.

e^7.2r = 2

Taking logs

7.2r = ln 2

r = ln2 / 7.2

r = 0.096

So the rate is 9.6%.

Thor invests $3000 in an account, with interest compounded continuously. If his investment doubles in value after 7.2 years, what interest rate is he earning? [Use the formla A = Pert and round answer to the nearest tenth.]A) 8.5%B) 9.6%C) 12.3%D) 14.0%

Thor invests $3000 in an account, with interest compounded continuously. If his investment doubles in value after 7.2 years, what interest rate is he earning? [Use the formla A = Pert and round answer to the nearest tenth.]

A) 8.5%

B) 9.6%

C) 12.3%

D) 14.0%