Using area and proportions, it is found that the smallest number of tiles that he will need to order is 300.
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The area of a rectangle of length l and width w is given by:
[tex]A = lw[/tex]
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Thus, the area of the floor is, in square metres:
[tex]A = lw = 10(6) = 60[/tex]
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[tex]\frac{60}{0.2} = \frac{600}{2} = 300[/tex]
A similar problem is given at https://brainly.com/question/10489198