# Math Help - Interest Rate Help

1. ## Interest Rate Help

Hello Everyone,

Can someone please tell me if the following is correct?

2. I'm a little troubled why you bothered to turn the values into percents. What would you do if it was $150,000 and there was another$50,000 @ 15%?

3. Hi there,

It happened to be convenient since the total was 100 k.
Can someone confirm if the final answer is correct?

4. i haven't checked your arithmatic but the sum you wrote down will give the right answer. (but only in this case as TKhunny pointed out)

5. thank you sir.

6. I just have to struggle with this. Which part did you do incorrectly on purpose! A very. very large part of success is personal confidence. Learn the facts. Execute a rational algorithm. Know what you are doing on each step along the way. Check you work. Move on. (You may wish to pay up you E&O Insurance)

More generally: $\frac{30(0.30) + 20(0.25) + 50(0.20)}{30 + 20 + 50}$

The percentages can take care of themselves.