Question

8. The top surface of a table has the shape of a trapezium. The parallel sides of the trapezium are 85
and 63 cm and perpendicular distance between these sides is 36 cm. Calculate its area and find the
cost of polishing the surface at the rate of 0.50 per cm?​

Answer 1

(Diagram is given in attachment)

Given:

• AB = 85 cm
• CD = 63 cm
• DE = 36 cm
• Cost of polishing = ₹0.50 per cm²

To find:

1. Area = ?
2. Cost of polishing = ?

Method:

$\sf{Area \: of \: Trapezium = \dfrac{1}{2} \times (Base_1 + Base_2) \times Height}$

$\longrightarrow \: \sf{Area \: of\: trapezium = \dfrac{1}{2} \times (AB + BC) \times DE}$

$\longrightarrow \: \sf{Area\: of\: trapezium= \dfrac{1}{2} \times (85+63) \times 36}$

$\longrightarrow \: \sf{Area\:of\:Trapezium= 18(85+63)}\\\\\\\longrightarrow \: \sf{Area\:of\:Trapezium=18(148)}\\\\\\\longrightarrow \: \large{\bf{\underline{Area\: of\: Trapezium = 2664~ cm^{2}}}}$

$\rm{Now \: for \: finding\: the\: cost\: of \: polishing,}$

$\sf{1\:cm^{2} = Rs \:0.50}\\\\\\\sf{For\: 2664 \: cm^{2},}\\\\\sf{2664 \times 0.50}\\\\= \large{\boxed{\bf{Rs\: 1332}}}$

Therefore, total cost of polishing = ₹ 1332

Answer 2

Answer:

area of trapezium=2664cm

total cost of polishing=RS 1332