Multiple choice

12 men and 16 women together can complete a work in 26 days while 10 women and 18 children together can complete the work in 20 days. Also, 8 men and 16 children can complete the work in 25 days. 1 man, 1 woman and 1 child start the work and from 2nd day onwards every day 1 new man, 1 new woman and 1 new child join the work. On which day the work shall be completed?

  1. 20th day

  2. 21st day

  3. 22nd day

  4. None of the above

  5. Cannot be determined
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let m, w, c be daily work of 1 man, 1 woman, 1 child. From given: 12m + 16w = 1/26, 10w + 18c = 1/20, 8m + 16c = 1/25. Solving this system and finding m + w + c, then using the pattern of work (n(n+1)/2 × (m+w+c) = 1), we get n = 21.

Keep practicing — related questions