Question

Tatiana invests $1300 in one account and $2400 in an account paying 3% higher interest. At the end of the year she had earned $183 I’m interest. At what rate did she invest?$1300 invest at ____%$2400 invested at ____%

Answer 1

Tatiana invests $1300 in one account with rate r

and $2400 in an account paying 3% higher interest (rate: r+0.03)

At the end of the year she had earned $183 In interest:

`1300r+2400(r+0.03)=183`

Use the equation above to solve r:

`\begin{gathered} 1300r+2400r+72=183 \\ 3700r+72=183 \\ 3700r+72-72=183-72 \\ 3700r=111 \\ \\ (3700)/(3700)r=(111)/(3700) \\ \\ r=0.03 \end{gathered}`

Then, Use the value of r to find the interest rate of second account:

`r+0.03=0.03+0.03=0.06`

Then, multiply each rate you get for first and second account by 100 to get the invest rate in %

$1300 invest at 3%$2400 invested at 6%