
Beth B. answered 02/17/21
Semester Exam Award Winner for Finite Math at SIUC
71 people
Total admissions sales = $136.25
Let C = the number of children
Let A = the number of adults
C + A = 71
1.25C + 2.50A = 136.25
C+ A = 71
-A -A
C = 71 - A
We will substitute (71 - A) into the second equation for C.
1.25(71 - A) + 2.50A = 136.25
88.75 - 1.25A + 2.50A = 136.25
88.75 + 1.25A = 136.25
-88.75 -88.75
1.25A = 47.50
÷ 1.25 ÷ 1.25
A = 38 adults
To find the number of children, you just plug the 38 into the first equation.
C + A = 71, so C + 38 = 71
-38 -38
C = 33 children
Check our answer:
33 + 38 = 71
71 = 71
1.25C + 2.50A = 136.25
1.25(33) + 2.50(38) = 136.25
41.25 + 95.00 = 136.25
136.25 = 136.25