Question

find the cost of painting the whole surface area of a box where lengthe is 60 cm breadth is 40 cm and heighti in 30 cm​

Answer 1

Total Surface area formula : 2( lb + bh + hl )

where h is the height, l is the length and b is the breadth

Now ,

2( 60 x 40 + 40 x 30 + 30 x 60 )

2 ( 2400 + 1200 + 1800)

2 ( 15400 )

= 30800 cm^2

=> 3.08 m^2

Now, Multiply the cost

if in m^2 then multioly with 3.08

and

if in cm^2 yhen multiply with 30800

Answer 2

● Answer -

Cost of painting = 270 Rs

● Explanation

Total outer surface area of the box is -

TSA = 2 (Ib + Ih + bh)

TSA = 2 (60×40 + 60×30 + 40×3)

TSA 10800 sq.cm

Cost of painting outer surface of box is -

Cost of painting = 10800 × 50/20

Cost of painting = 27000 p

Cost of painting = 270 Rs

Hence, cost of painting outer surface of box is Rs. 270

Hope it helps

:)