Question

Peter has money in two savings accounts. One rate is 9% and the other is 11 %. If he has $400 more in the 11 % account and the total interest is $117. how much isinvested in each savings account?

Answer 1

Let x be the money Peter has invested in the 9% rate account, and y be the money in the 11% account, then we can set the following system of equations:

`\begin{gathered} y=x+400, \\ 0.09x+0.11y=117. \end{gathered}`

Substituting the first equation in the second one we get:

`0.09x+0.11(x+400)=117.`

Solving for x we get:

`\begin{gathered} 0.09x+0.11x+44=117, \\ 0.2x=117-44=73, \\ x=(73)/(0.2), \\ x=365. \end{gathered}`

Substituting x=365 in the first equation we get:

`y=365+400=765.`

Answer: Peter has $365 invested in the 9% account and $765 in the other one.