How to find the minimum cost? Thanks!

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1 Answer

30 large tiles for $135

Explanation:

Let's first look at the cost of each tile per area covered.

Small tiles, 4x4, # =>"16 inches"^2=>($3.50)/16=$0.21875# per square inch

Large tiles, 6x12, # =>"72 inches"^2=>($4.50)/72=$0.0625# per square inch

And so we want to use as many large tiles as possible to cover the most area possible.

The mosaic must be at least 3 feet tall (36 inches) and 5 feet wide (60 inches).

Using large tiles, let's see how many we need to reach the proper height:

#"required inches high"/"tile height"=36/6=6# tiles.

And let's see how many large tiles we need to achieve the proper width:

#"required inches wide"/"tile width"=60/12=5# tiles.

And so to cover the entire area, we need:

#6xx5=30# tiles.

This will cost:

#30xx$4.50=$135.00#