Planning ahead for Katie's freshman year of college, her parents invested $8,000 into an account at 6% to be compounded annually. After how many years will the account be worth $16,098 ?
I used the formula A(t) = A(1 +(r/))^nt

Question

Planning ahead for Katie's freshman year of college, her parents invested $8,000 into an account at 6% to be compounded annually. After how many years will the account be worth $16,098 ? 
I used the formula A(t) = A(1 +(r/))^nt

sphott51 · Answer

I think that's the right formula

alexrobin13 · Answer

I'm not sure if you just mistyped the formula but it is A(t) = A(1 +(r/n))^nt

alexrobin13 · Answer

Plug in the values and let me know if you get the answer youre looking for

sphott51 · Answer

I plugged in 16,098 = 8,000(1 + (.06/1)) ^1t

erak · Answer

Okay, so what do you think would be your first steps for isolating t?

alexrobin13 · Answer

divide 8000 over and go from there

sphott51 · Answer

I divided it  and I got 2.01

erak · Answer

Okay the way I would do it would be with logarithms, like so:
$$\frac{ \log2.01 }{\log 1.06 }$$ You should get approximately 12 years.

sphott51 · Answer

It isn't logs?

sphott51 · Answer

Oh nevermind haha

erak · Answer

The function is called a logarithm. It's "log" on a calculator.

sphott51 · Answer

I got 11.98

erak · Answer

Yeah, so if you didn't round and used 2.01225 instead, you would have gotten basically 12 years. You can double check that with the original equation.

sphott51 · Answer

I could round it with the .9 of 11.98

erak · Answer

Yeah, just list your answer as "approximately 12 years."