A man invested some amount at 6% interest rate and some amount at 9% interest rate. If he put Php12,000 more in the second investment than in the first investment and his annual income from both investments is Php4,830 how much did he invest at each rate?

Sep 18, 2015

Php22000 and Php34000

Explanation:

Let the lower interest principal be x. Then higher interest principal = x +12000.

Given total interest received at year end is 4380,

6% of x + 9% of (x+12000) =4380
or, $\frac{6 x + 9 x + 108000}{100} = 4380$
or, $15 x = 438000 - 108000$
Hence, $x = \frac{330000}{15} = 22000$

Therefore, sum invested at 6% is Php22000 and that at 9% is Php34000