Q. |
A and B can complete a piece of work in 10 and 20 days respectively. If they work in alternate days, starting with A, in how many days will the work be completed? |
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A. 10 |
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B. 11 |
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C. 12 |
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D. 13 |
Let the total work to be completed = 20 units (LCM of 10 & 20)
On the first day, A can do 2 units of work
On the second day, B can do 1 unit of work
3 units of work will be completed in 2 days
18 units of work will be completed in 12 days.
Next day A will complete 2 units.
Hence total number of days = 12 + 1= 13 days