Question

At the city museum, child admission is $5.20 and adult admission is $8.30 . On Monday, three times as many adult tickets as child tickets were sold, for a total sales of $1173.90

Answer 1

Write the equations:
`5.20c+8.30a=1173.90 \\ c=3a`

Substitute for c:
`5.20(3a)+8.30a=1173.90`

Solve for a:
`5.20(3a)+8.30a=1173.90 \\ 15.60a+8.30a=1173.90 \\ 23.90a=1173.90 \\ a=49`

There were about 49 adult tickets sold. There were about 147 child tickets sold.