Lena is tiling a square floor with each

side 3 metres long. Tiles cost $45 per
square metre.
Which calculation gives the total cost of
tiling the floor (in dollars)?

First calculate area of square room

side = 3m
Area = side*side m²

From unit price = $45/m², calculate
Total Cost = unit price * area

30

45x6

To find the total cost of tiling the floor, we need to calculate the area of the square floor and then multiply it by the cost of each square meter.

The area of a square can be calculated by multiplying the length of one side by itself. In this case, since each side of the square floor is 3 meters long, the area would be 3 * 3 = 9 square meters.

Now, to find the total cost, we multiply the area of the square floor (9 square meters) by the cost of each square meter ($45). Therefore, the calculation that gives the total cost of tiling the floor in dollars would be:

9 square meters * $45/square meter = $405

So, the total cost of tiling the floor would be $405.