Question

370 people bought tickets to a fair. Adult tickets were $7 and kids tickets were $3. Total revenue was $1750. Child tickets are x while adult tickets are y. How many child tickets were sold?
x+y=370
3x+7y=1750

Answer 1

210 children tickets are sold

Solution:

Let "x" be the number of child tickets sold

Let "y" be the number of adult tickets sold

Cost of 1 adult ticket = $ 7

Cost of 1 child ticket = $ 3

Given that 370 people bought tickets to a fair

number of child tickets sold + number of adult tickets sold = 370

x + y = 370 ------ eqn 1

Total revenue was $1750. Therefore,

number of child tickets sold x Cost of 1 child ticket + number of adult tickets sold x Cost of 1 child ticket = 1750

$x \times 3 + y \times 7 = 1750$

3x + 7y = 1750 ------ eqn 2

Let us solve eqn 1 and eqn 2

From eqn 1,

x = 370 - y ------- eqn 3

Substitute eqn 3 in eqn 2

3(370 - y) + 7y = 1750

1110 - 3y + 7y = 1750

4y = 1750 - 1110

4y = 640

y = 160

From eqn 3,

x = 370 - 160

x = 210

Thus 210 children tickets are sold