PROBLEM
The admission fee at an amusement park is $1.50 for children and $4 for adults. On a certain day, 303 people entered the park, and the admission fees collected totaled 792.00 dollars. How many children and how many adults were admitted?
SOLUTION
LET C BE THE NUMBER OF CHILDREN AND A BE THE NUMBER OF ADULTS
SO, EQUATION FOR THE NUMBER OF PEOPLE: C + A = 303
AND EQUATION FOR THE ADMISSION FEES: 1.5*C + 4*A = 792
MULTIPLY THE PEOPLE EQUATION BY -4 SO YOU CAN ELIMINATE A, THEREFORE
-4 ( C + A = 303) BECOMES -4*C - 4*A = - 1212
1.5*C + 4*A = 792
-2.5*C = - 420
C = 168
SUBSTITUTE THE VALUE FOR C INTO THE EQUATION FOR PEOPLE: 168 + A = 303; A = 303 - 168, A = 135
THEREFORE, 168 CHILDREN WERE ADMITTED AND 135 ADULTS WERE ADMITTED.