a small fair changes an admission fee for children and adults. The cost for admission is $3 per adult and $2 per child. On a certain day, total sales were $900, and 350 people attended the fair. How many children attended the fair that day?
We need to make a system of equations. A=Adults and C=Children. A+C=350; this means how many people are there. 3A+2C=900; this deals with money. We need to eliminate a variable, let's eliminate C by multiplying the first equation by -2. -2a-2C=-700 3A+2C=900 A=200 This means there was 200 adults, which means there had to be 150 children.
