Tanya bought two adult tickets and one children's ticket to a movie for $13.90 . Li bought five adult tickets and three children's tickets for $36.70 . Find the cost of one adult ticket and the cost of one children's ticket.

Sam is a waiter at a local restaurant where he earns wages of $5 per hour sam figures that he also eams about $3 in tips for each person he serves sam works 6 hours on a particular day. if n represents the number of people sam serves that day, which of the following functions could sam use to figure ehis total earings for the do o a. en) = 30 o b. en) = 5n+ 18