If Mike invested it all at 6%, his earnings would have been .06*$2000 = $120. He earned $24 more than that. His additional earnings were at an additional rate of 8% - 6% = 2%, so he must have had $24/.02 = $1200 invested at 8%.

**Mike's investment was $1200 at 8% and $800 at 6%**.__Check__.08*1200 + .06*800 = 96 + 48 = 144 If you want to solve this algebraically, you can let "h" stand for the investment at the high interest rate. .08h + .06(2000-h) = 144 .08h + 120 - .06h = 144 (use the distributive property to eliminate parentheses) .02h + 120 = 144 (collect terms) .02h = 24 (subtract 120) h = 24/.02 = 1200 (if you read the above, this should look familiar)