8. The top surface of a table has the shape of a trapezium. The parall

1.	8. The top surface of a table has the shape of a trapezium. The parallel sides of the trapezium are 85and 63 cm and perpendicular distance between these sides is 36 cm. Calculate its area and find thecost of polishing the surface at the rate of 0.50 per cm?
Answer» (Diagram is GIVEN in attachment) Given: AB = 85 cm CD = 63 cm DE = 36 cm Cost of polishing = ₹0.50 per cm² To FIND: Area = ? 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

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

Answer»

(Diagram is GIVEN in attachment)

Given:

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

To FIND:

Area = ?
Cost of polishing = ?

Method:

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

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

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

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

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

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