A and B can finish a piece of work in 15 days and 20 days respectively. If A and B work on alternate days (A starts the work), how many days will it take to complete the work?
Given:
A can do work in 15 days
B can do work in 20 days
Formula Used:
Work = Rate × Time
Solution:
Total work = LCM of 15 and 20 = 60 units
A’s 1 day work = = 4 units
B’s 1 day work = = 3 units
Work done in 2 days = 4 + 3 = 7 units
In 16 days (8 cycles): 7 × 8 = 56 units
Remaining work = 60 − 56 = 4 units
A completes remaining work in 1 day.
Total days =16 +1 = 17 days
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60 Mins English English20 Questions40 Marks12 Mins English English80 Questions160 Marks60 Mins EnglishA and B can finish a piece of work in 15 days and 20 days respectively. If A and B work on alternate days (A starts the work), how many days will it take to complete the work?
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