Question

help me please answer it​

Answer 1

Answer:

External length (l) of bookshelf=85㎝

External breadth (b) of bookshelf=25㎝

External height (h) of bookshelf=110㎝

External surface area of book shelf while leaving out the front face of the shelf=lh+2(lb+bh)

=(85×110)+2(85×25+25×110)

=9350+9750

=19100㎠

Area if front face=(85×110)−75×100+2(75×5)

=1850+760=2600㎠

Area to be polished=19100+2600=21700㎠

Cost of polishing=Rs. 21700×0.20=Rs.4340

Length, breadth and height of each row of bookshelf are

75㎝,20㎝ & 30㎝ respectively. From the figure Area to be painted in 1 row=2(l+h)b+lh

=2(75+30)20+75×30

=6450㎠

Area to be painted in 3 rows=3×6450=19350㎠

Total cost of painting=Rs.(19350×0.1)=Rs. 1935

Total expenses=Rs.(4340+1935)=Rs. 6275