First, we must let: x = number of tickets intended for adults y = number of tickets intended for children.
a. Write in terms of x the number of tickets for children Solution: x + y = 28 ⇔ y = 28 - x (equation 1) To answer in terms of x: no. of tickets for tickets for children = 28 - x
b. the amount spent on tickets for adults Solution: $30 is the cost of ticket per adult and there are x number of tickets intended for adults. Therefore, amount spent on ticket for adults = 30x
c. the amount spent on the tickets. Solution: $ 15 = cost of ticket per child $ 30 = cost of ticket per adult
total amount spent on tickets = 30x + 15y ⇒ (equation2) substitute equation 1 to equation 2. (equation 1) y = 28 - x (equation 2) total amount spent on tickets = 30x + 15y total amount spent on tickets = 30x + 15(28-x) total amount spent on tickets = 30x + 420 - 15x total amount spent on tickets = 15x + 420
