mathword problem
posted by chris .
admission to a park is $5 for an adult ticket and $1 for a child. If $100 was collected and 28 admissions were sold on a day, how many tickets were sold and how many child tickets were sold

Let x = adult and Y = child tickets.
x + y = 28
x = 28  y
5x + y = 100
Substitute 28y for x in third equation and solve for y. Insert that value into the first equation and solve for x. Check by inserting both values into the third equation. 
from a board 38 1/2 inches long pete cut a piece 17 5/8 inches long how long was the remaining piece