Christina ordered 20 pizzas. she ordered some with pepperoni and some with cheese. 50% of that pizza that we ordered had pepperoni. how many pizzas to order with the pepperoni?

Mikael, hema and 5 friends will run an event. they will wear either a red shirt or red baseball hat during the event. they want to spend exactley $40. shirts cost $8 each and caps cost $4 each.