Question

Tina wants to save money for school. Tina invests $1000 in an account that pays an interest rate of 8%. How many years will it take for the account to reach $1300? Round your answer to the nearest hundredth.

Answer 1

Okay, so money is official ridiculous to calculate.
Interest rate for this you need a thing called Compound Interest formula which is
\[F=P(1+I)^{t}\]
F = future amount
P = principle amount (initial amount, 1000 in your case)
I = interest rate as a decimal (8% = 0.08)
t = time in years

So you need to solve this equation for t, plug in your numbers, and you'll have your answer.
Solving for t:
\[1300=1000(1.08)^{t}\] \[{1300 \over 1000} = 1.08^t\] \[\ln 1.3 = t\] \[{{\ln 1.3} \over {\ln 1.08}} = t\] \[t = 3.41\]

So your answer is it takes 3.41 years to get $1300 at an interest rate of 8% from an initial amount of $1000