Question

$dont \: dare \: to \: spam$


A floral design on a floor is made up of 16 tiles which are triangular, the sides of the triangle being 9 cm, 28 cm and 35 cm (see Fig. 12.18). Find the cost of polishing the tiles at the rate of 50p per cm?​

Answer 1

Hi there!

Your Answer :- ₹705.60

Solution :-

Semi Perimeter = ( a + b + c ) / 2.

a = 35cm, b = 28cm, c = 9cm.

$\sf\red{\frac{35 + 28 + 9}{2}} \: = \: \green{\frac{72}{2} \:} = \pink{36}$

Applying Herons Formula :-

$\sf \sqrt{36 \times 1 \times 8 \times 27}$

Taking Common.

$\sf\orange{3 \times 2 \times 2 \times 3 \sqrt{6} }$

$\sf\green{36 \sqrt{6} }$

And the value of root (6) = 2.45

$\sf\pink{36 \times 2.45}$

$\sf\blue{88.2 \: {cm}^{2} }$

Multiply the Area By Cost.

Cost = 50 paise = ₹0.5

$\sf88.2 \times 0.5 =44.1 \: rupees$

Tiles are given = 16.

So,

$\sf\purple{44.1 \times 16 = 705.60 \: rupees}$

So, the Answer is ₹705.60