i am stuck with the follwoing question: floor is 2.4m by 1.6m. all the tiles are 20cm cquare. one layer of border tiles is placed around the edge. how many tiles are needed to fill in the middle?
2007-12-16 05:02:44 · 5 answers · asked by Tin T 2 in Science & Mathematics ➔ Mathematics
Number of tiles along length = 240 / 20 = 12
Number of tiles along breadth = 160/20 = 8
Total no. of tiles = 12 x 8 = 96
2007-12-16 19:05:33 · answer #1 · answered by Como 7 · 3⤊ 1⤋
The number of tiles needed to fill the entire floor is
( 2.4 m ) ( 1.6 m ) / ( .20² ) = 96
The number of tiles needed for the border is
( 2.4 m ) / (.20) = 12 on each long side ( 24 total )
( 1.6 - .20 - .20 ) / ( .20 ) = 6 on each short side ( 12 total )
That's 36 tiles for the border, leaving 60 tiles for the rest of the floor.
Cross check: ( 2.4 - .40 ) ( 1.6 - .40 ) / ( .20² ) = 60
2007-12-16 05:14:41 · answer #2 · answered by jgoulden 7 · 2⤊ 2⤋
60
2007-12-16 12:29:38 · answer #3 · answered by Anonymous · 0⤊ 1⤋
Since border 20 cm wide the area to be filled is (2.4-0.4) x (1.6-0.4) =2.0 x 1.2 = 2.4 sq metres. Now area of one tile =0.2 x0.2 =0.04 sq metres.
Therefore number of tiles to fill centre = 2.4/0.04 = 60 tiles.
2007-12-16 06:51:35 · answer #4 · answered by Anonymous · 0⤊ 1⤋
guess somewhere between 59 and 61
2007-12-16 05:18:42 · answer #5 · answered by Clint Eastwood 2 · 0⤊ 1⤋