Brandon invests some of his retirement savings in a fund earning 7% simple interest and invests twice as much in a fund earning 9% simple interest. If he earns $550 combined interest on the accounts, how much does he have in the 7% account?

Question

anonymous · Answer

So you need a good algebraic equation to solve this.  If s is the amount in his savings, then s/3 would be one third of it and 2s/3 would be two thirds of it.  s/3 earned 7% and 2s/3 earned 9%, and together those percentages add to $550.  The equtation then would be (s/3 * .07) + (2s/3 * .9) = $550.

anonymous · Answer

So you just need to solve that equation to get the answer.

anonymous · Answer

ok thank you

anonymous · Answer

Understand?

anonymous · Answer

no this is wronng

anonymous · Answer

Ah, yep.  Typo there on the decimal.  Should be .09 not .9, which you should have recognised...

Do you need help solving the equation?