Question

At his son's birth, a man invested $2,000 in savings at 6% for his son's college education.

Approximately how much, to the nearest dollar, will be available in 19 years? (Do not use comma placeholder in response.)

Rounded to the nearest year, approximately how long will it take for the man’s investment to double?

Answer 1

value in 19 years: $6051

years to double: 12

Answer 2

now, this is assuming the 6% is at simple interest rate.

`~~~~~~ \textit{Simple Interest Earned Amount} \\\\ A=P(1+rt)\qquad \begin{cases} A=\textit{accumulated amount}\\ P=\textit{original amount deposited}\dotfill & \$2000\\ r=rate\to 6\%\to (6)/(100)\dotfill &0.06\\ t=years\dotfill &19 \end{cases} \\\\\\ A=2000[1+(0.06)(19)]\implies A=2000(1.54)\implies A=3080 \\\\[-0.35em] ~\dotfill`

`~~~~~~ \textit{Simple Interest Earned Amount} \\\\ A=P(1+rt)\qquad \begin{cases} A=\textit{accumulated amount}\dotfill & \$4000\\ P=\textit{original amount deposited}\dotfill & \$2000\\ r=rate\to 6\%\to (6)/(100)\dotfill &0.06\\ t=years \end{cases} \\\\\\ 4000=2000[1+(0.06)(t)]\implies \cfrac{4000}{2000}=1.06t \\\\\\ 2=1.06t\implies \cfrac{2}{1.06}=t\implies 1.89\approx t\implies \stackrel{\textit{rounded up}}{2\approx t}`