Question 124447
.65X+.40(25-X)=14
.65X+10-.40X=14
.25X=14-10
.25X=4
X=4/.25
X=16 $.65 CARDS WERE SOLD.
25-16=9 $.40 CARDS  WERE SOLD 
PROOF
.65*16+9*.40=14
10.4+3.6=14
14=14