Time and Work with Explanation

Q22. Q can finish a work in 20 days while P in 15 days. If the work together 4 days, then find the fraction work that is left?

A. B.
C. D.

Q23. Nikki is 25% more efficient than Tina. Tina alone can build a craft in 20 days. Find the number of days taken by Nikki to finish the same piece of work?

A. 15 B. 17
C. 18 D. 16

Q24. Worker P is 50% as efficient as worker Q. Worker R does half of the work done by P and Q together. If R alone does the work in 40 days, then P, Q, and R together can do the work in?

A. 20 days B. 25 days
C. 13 days D. 15 days

Q25. A machine A can produce one thousand cars in 8 hours, machine B can produce the same numbers of cars in 10 hours, and machine C can produce them in 12 hours. All the machines started at 9 AM, but machine A is closed at 11 AM, and the remaining machines complete the work. Find the time at which the work will be completed?

A. 1:00 PM B. 12:45 PM
C. 12:25 PM D. 11:30 AM