Admission to Science World is $5.50 more for an adult than for a child. Admission to the museum for Barbie and Ken and their five children costs $39. Find the cost of admission for each adult and each child.

1) a=c+5.5
2) 2a+5c=39 


2(c+5.5)+5c=39
7c=28
c=4 

Adults pay $9.50, Children pay $4