Tristan is laying 12" x 18" tiles on the lab floor. If the lab measures 15 feet by 18 feet, how many tiles does Tristan need, assuning there's no waste.

1 answer

The lab would measure
180 inches by 216 inches

case 1: longer side of tile along longer side of floor
216/18 = 12
180/12 =15
number of tiles = 12x15 = 180

case 2: shorter side of tile along the longer side of floor
216/12 = 18
180/18 = 10
number of tiles = 10x18 = 180

Of course we had to get the same answer, since division was exact either way, thus no waste

other way:
area of 1 tile = 12" by 18"
= 1ft by 1.5 ft
= 1.5 ft^2
area of floor = 15(18) or 270 ft^2

number of tiles = 270/1.5 = 180