A can do a work in 15 days and B in 20 days. If they work on it together for 4 days, then the fraction of work that is left is:
Given:
A can do a work in 15 days and B in 20 days
They work on it together for 4 days
Formula used:
Total work = Number of days × 1 day's work (Efficiency)
Calculation:
∴ Total work = LCM (15, 20) = 60 unit
1 day's work of A = 60/15 = 4 unit
1 day's work of B = 60/20 = 3 unit
1 day's work of (A + B) together = 4 + 3 = 7 unit
Now,
They work on it together for 4 days
∴ Total work completed in 4 days = 4 × 7 = 28 unit
Work left = 60 - 28 = 32
The fraction of work left
English
100 Questions
100 Marks
60 Mins English English100 Questions100 Marks60 Mins English English20 Questions20 Marks8 Mins English
A can do a work in 15 days and B in 20 days. If they work on it together for 4 days, then the fraction of work that is left is:
A and B complete a work in 15 days. If A alone can do it in 17 days, then B alone can do two-third of the same work in ______________ days.
An electric pump can fill a tank in 6 hours. Due to a leakage in the tank, it takes 7 hours to fill the tank. How much time will this leak take to empty the full tank if water does not get in or out of the tank through any other point during this period?
An electric pump can fill a tank in 6 hours. Due to a leakage in the tank, it takes 7hours to fill the tank. How much time will this leak take to empty the full tank if water does not get in or out of the tank through any other point during this period?