Answer:
Jimmy purchased 8 of the children's ticket and 7 of the adult's ticket.
Step-by-step explanation:
Let c = children tickets
Let a = adult tickets
<u>Given the following data;</u>
Number of tickets = 15
Total amount spent = $140
Cost of each children ticket = $7
Cost of each adult ticket = $12
*Translating the word problem into an algebraic equation (system)*
<em>For the total number of tickets;</em>
.........equation 1
<em>For the total amount spent;</em>
..........equation 2
*Solving the linear equation by using the substitution method*
<em>Making c the subject in equation 1:</em>
.......equation 3
<em>Substituting "c" into equation 2;</em>
<em>Simplifying the equation, we have;</em>
<em>Rearranging the equation, we have;</em>

a = 5 (For the $12 adult ticket).
To find the number of children tickets;
Substituting "a" into equation 3;

c = 8 (For the $7 children ticket).