Basic Math/finacial literacy
Your bed room is 14 feet by 10 feet and your sister room is 14 feet by 10 feet. If you are going to paint both rooms the same color and the paint covers 250 square feet per gallon.How much paint will you need to buy if your painting the walls and the ceilings? Assuming the ceiling is 8 feet high.
First, just want to make sure both rooms are the exact same size and it's not a typo. If that's the case, then there are 4- 14x8 walls, 4- 10x8 walls and 2- 14x10 ceilings to paint (of course, these rooms apparently do not have door or windows or you will be painting over them). 14x8x4= 448
10x8x4= 320 and 14x10x2= 280. 448+320+280= 1048 sq ft to paint. Each gallon covers 250sf so 1048/250= 4.19. Unless you can buy a quart, you'll need 5 gallons of paint. Or, since the rooms probably have doors and windows, you could get away with 4 gallons. But, the answer the teacher/book wants is probably 4.19