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A floral design on a floor is made up of 16 tiles, each triangular in shape having sides 16 cm, 12 cm, and 20cm. Find the cost of polishing the tiles at Re 1 per sq cm.

Let the sides of the triangle be:

a = 16 cm

b = 12 cm

And,

c = 20 cm

Now we have to find out the value of s:

s =

=

= = 24 cm

We know that,

Area of triangle =

Therefore,

Area of triangular tile =

=

= 2 × 2 × 2 × 2 × 2 × 3

= 96 cm^{2}

Therefore,

Area of one tile = 96 cm^{2}

Hence,

Area of 16 such tiles = 96 × 16 = 1536 cm^{2}

Now,

Cost of polishing the tiles per square cm = Rs. 1

Therefore,

Total cost of polishing the tiles = 1 × 1536

= Rs. 1536

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