Alien Adventures

Mission 04

They're almost ready! Your mission is to give each alien child 1 coloring book and 10 crayons to keep them busy during the trip. There are 18 alien children and you have enough coloring books, but you only have 145 crayons. How many more crayons do you need?

Need a hint? Think about the total number of crayons you need and how many you have.