Answer:
Explanation:
(a) Let L represent the length of the floor. The length is 3 times the width, so we have L = 3W, or W = L/3.
P = 2(L+W) . . . . the formula for the perimeter of a rectangle
Filling in the known values, we have ...
40 = 2(L +L/3)
20 = (4/3)L . . . . divide by 2 and collect terms
15 = L . . . . . . . . multiply by 3/4
The length of the floor is 15 m.
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(b) From above, the width is ...
W = L/3 = (15 m)/3 = 5 m.
The area is given by the formula ...
A = LW = (15 m)(5 m)
A = 75 m²
The area of the floor is 75 square meters.