Answer
She invested 900 dollars at 3% interest, so she invested 2150 dollars at 5% interest.
Work Step by Step
Let X represent the amount of money invested at 3% interest.
After a year, she received 3% of the X amount invested as interest.
She received 3% $\times$ X = 0.03X.
Also, she invested 1250 more than X, or X + 1250 at 5% interest.
After a year, she received 5% of the X + 1250 as interest.
She received 5% $\times$ (X + 1250) = 0.05X + 62.50
Her total yearly interest was 134.50
So: 0.03X + 0.05X + 62.50 = 134.50
0.08X = 72
Divide both sides by 0.08:
X = 900
She invested 900 dollars at 3% interest.
She invested 1250 dollars more than X, or 900 dollars, at 5% interest, so she invested 2150 dollars at 5% interest.
