Question 124898
.07X+.05(10000-X)=644
.07X+500-.05X=644
.02X=644-500
.02X=144
X=144/.02
X=7200 ANSWER FOR THE AMOUNT INVESTED @ 7%.
10000-7200=2800 INVESTED @ 5%.
PROOF.
.07*7200+.05*2800=644
504+140=644
644=644