Question 717623
A+C=100
A=100-C
4A+2.5C=355
4(100-C)+2.5C=355
400-4C+2.5C=355
-1.5C=355-400
-1.5C=-45
C=-45/-1.5
C=30 CHILDREN'S TICKETS WERE SOLD.
A=100-30
A=70 ADULT TICKETS WERE SOLD.
PROOF:
4*70+2.5*30=355
280+75=355
355=355