SOLUTION: Lean made a scale drawing design for a tile floor. It measured 9 inches in length and 15 inches in width. The actual width of the tile floor will be 75 inches. If Leah uses 3-inch

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Question 182910: Lean made a scale drawing design for a tile floor. It measured 9 inches in length and 15 inches in width. The actual width of the tile floor will be 75 inches. If Leah uses 3-inch square tiles to tile the floor, and the floor is proportional to her drawing, how many tiles will she need?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
In words:
(width of floor on drawing) / (actual width of floor) =
(width of tile on drawing) / (actual width of tile)
Now I'll plug in numbers that are given:
15%2F75+=+x%2F3
Multiply both sides by 75
15+=+25x
x+=+.6
On the drawing, a tile is .6 x .6 in2
How many of these tiles on the drawing does it take to cover
9 in x 15 in ?
9%2F.6+=+15 in
15%2F.6+=+25 in
The number of tiles on the drawing is 15%2A25+=+375
She will need 375 tiles -answer
check answer:
The actual tiles are 3 in x 3 in = 9 in2
375 tiles x 9 in2 / tile = 3375 in2
Now what is the actual area of the floor?
(length of floor on drawing) / (actual length of floor) =
(length of tile on drawing) / (actual length of tile)
9%2Fy+=+.6%2F3
27+=+.6y
y+=+45 in
The area of the floor is xy+=+45%2A75
45%2A75+=+3375 in2
OK