A closed wooden box of thickness 0.5 cm and length 21 cm, width 11 cm, and height 6 cm, is painted on the inside. The cost of painting is Rs 70. What is the rate of painting in rupees per sq. cm?

• thickness of box = 0.5 so dimension of box from inside = 20cm x 10cm x 5cm
  cost of painting = surface areaxrate -->70 = (2*10*20 + 2*10*5 +2*20*5)xrate
  --> rate=70/700 =0.1
• 13 years agoHelpfull: Yes(15) No(9)
• (A)0.7
  (B)0.5
  (C)0.1
  (D)0.2
  (E)0.8
  answer is C
• 13 years agoHelpfull: Yes(9) No(12)
• we have to take height as H - 0.5 !!!!
• 10 years agoHelpfull: Yes(0) No(5)