On a trip, the fare was 75¢ for each adult and 50¢ for each child. If 20 passengers paid $12.00, how many adults and children went?
Which of the following equations could not be used to solve the problem?

75x + 50(20 - x) = 1200
75(20 - x) + 50x = 1200
75x + 50x = 20(1200)

Im pretty sure the last equaion could not be used to solve. Am i right?

Question

On a trip, the fare was 75¢ for each adult and 50¢ for each child. If 20 passengers paid $12.00, how many adults and children went?
Which of the following equations could not be used to solve the problem?

75x + 50(20 - x) = 1200
75(20 - x) + 50x = 1200
75x + 50x = 20(1200)

Im pretty sure the last equaion could not be used to solve. Am i right?

anonymous · Answer

0.75x+ 50y= 12.00
x+y=20 use substition

igreen · Answer

None of them look correct because you need a separate variable for Adults and Children..

Like 

Adults = x
Children = y