defence exam Army Havildar SAC Mock Test Series 2025 Quantitative Aptitude Time and Work Work Efficiency
A and B working separately can do a piece of work in 16 days and 28 days, respectively. If they work on alternate days beginning with B. in how many days will the work be completed?
1
\(18\frac{1}{2}\)
2
\(20\frac{1}{2}\)
3
\(21\frac{1}{2}\)
4
\(19\frac{1}{2}\)