Question

Esmeralda invests $1900 in one account and $1100 in an account paying 4 % higher interest. At the end of one year she had earned $104 in interest. At what rates did she invest?

Answer 1

Let's use the variable x to represent the first interest, so the second will be represented by x + 0.04.

Since both interests added are equal to $104, we can write the following equation:

`\begin{gathered} 1900\cdot x+1100\cdot(x+0.04)=104 \\ 1900x+1100x+44=104 \\ 3000x=60 \\ x=(60)/(3000) \\ x=0.02 \end{gathered}`

So the first interest is 2% and the second one is 6%.