Answer:
17 adults, 13 students and 90 children
Explanation:
Solving by using Equations
in order to answer his question we have to create two equations
we first need to give each group of people a variable:
adults = x
student = y
children = z
first equation is for the total price
5x + 2y + 0.10z = 120
second equation is for the total number of people :
x + y+ z = 120
- in this case substitution and elimination method can not work as there are three unknown variable not two
in order for the total amount from the ticket sales to be exactly $120 , then the number of children have to be a multiple of 10 ( eg 0.10 * 10 = 10)
therefore they will be no decimal point
through the use of probability and trial and error
number of number of number of total cost
children adults students of tickets
--------- --------- ---------- ----------
90 1 29 $ 72
90 3 27 $ 78
90 5 25 $ 84
90 7 23 $ 90
90 9 21 $ 96
90 11 19 $102
90 13 17 $108
90 15 15 $114
90 17 13 $120
17 adults, 13 students and 90 children
we can test this put in the equation :
5x + 2y + 0.10z = 120
5 (17) + 2 (13) + 0.10 (90) = 120
also the other equation can be used to check if it is correct :
x + y+ z = 120
17 + 13 + 90 = 120
hence this answer is CORRECT