Working 5 hours a day, A can Complete a work in 8 days and working 6 hours a day, B can complete the same work in 10 days. Working 8 hours a day, they can jointly complete the work in how many days?
A. 3 days B. 4 days C. \(4.5\) days D. \(5.4\) days
Correct Answer: A
Explanation
Working 5 hours a day, A can complete the work in 8 days \(=5^{\star} 8=40\) hours Working 6 hours a day, B can complete the work in 10 days \(=6^{*} 10=60\) hours \((A+B)\) 's 1 hour's work \(=(1 / 40+1 / 60)\) \(=(3+2) / 120\) \(=1 / 24\) Hence, A and B can complete the work in 24 hours which is equal to 3 days.
