2018 · Q73
Walls (excluding roofs and floors) of 5 identical rooms having length, breadth and height 6 m, 4 m and 2.5 m respectively are to be painted. Out of five rooms, two rooms have one square window each having a side of 2.5 m. Paints are available only incans of 1 litre; and 1 litre of paint can be used for painting 20 square metres. The number of cans required for painting is
Elementary MathematicsMensuration
- A10
- B12
- C13
- D14
Explanation
Wall area = 5 rooms x 2(6 + 4) x 2.5 = 250 sq m; minus two windows of 2.5 x 2.5 = 12.5 sq m gives 237.5 sq m. Paint required = 237.5/20 = 11.875 litres, so 12 one-litre cans are needed. Hence option B.