Project ForgeGeneral Aptitude
Quantitative Aptitude
GATE 2010
Medium
5 skilled workers can build a wall in 20 days; 8 semi-skilled workers can build a wall in 25 days; 10 unskilled workers can build a wall in 30 days. If a team has 2 skilled, 6 semi-skilled and 5 unskilled workers, how long will it take to build the wall?
- A20 days
- B18 days
- C16 days
- 15 days
Explanation
One skilled worker's rate = 1/(5x20) = 1/100 wall/day. One semi-skilled worker's rate = 1/(8x25) = 1/200. One unskilled worker's rate = 1/(10x30) = 1/300. Team rate = 2/100 + 6/200 + 5/300 = 0.02+0.03+0.01667 = 1/15 wall/day. Time = 15 days.
Source: GATE ME 2010 (2010)
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