13 Views

Question : A and B can complete a piece of work in 13 and 17 days respectively. A begins to do the work, and they work alternatively one at a time for one day each. The whole work will be completed in:

Option 1: $17 \frac{11}{17}$ days

Option 2: $17 \frac{17}{19}$ days

Option 3: $14 \frac{11}{17}$ days

Option 4: $11 \frac{11}{17}$ days


Team Careers360 11th Jan, 2024
Answer (1)
Team Careers360 20th Jan, 2024

Correct Answer: $14 \frac{11}{17}$ days


Solution : Time taken by A to complete the work = 13 days
Part of work done by A alone in a day = $\frac{1}{13}$
Time taken by B to complete the work = 17 days
Part of work done by B alone in a day = $\frac{1}{17}$
Work done by A and B in the first 2 days if they work alternatively
= $\frac{1}{13}$ + $\frac{1}{17}$
= $\frac{13+17}{13×17}$
= $\frac{30}{221}$
Work done by A and B in 14 days = $\frac{7×30}{221}$ = $\frac{210}{221}$
Remaining work = $1-\frac{210}{221}=\frac{221-210}{221}$ = $\frac{11}{221}$
So, the time taken by A to complete the rest = $\frac{\frac{11}{221}}{\frac{1}{13}}$ = $\frac{11}{17}$
Thus, the total time taken by A and B to complete the work when they work alternatively
= $14\frac{11}{17}$ days
Hence, the correct answer is $14\frac{11}{17}$ days.

SSC CGL Complete Guide

Candidates can download this ebook to know all about SSC CGL.

Download EBook

Know More About

Related Questions

TOEFL ® Registrations 2024
Apply
Accepted by more than 11,000 universities in over 150 countries worldwide
Manipal Online M.Com Admissions
Apply
Apply for Online M.Com from Manipal University
View All Application Forms

Download the Careers360 App on your Android phone

Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile

150M+ Students
30,000+ Colleges
500+ Exams
1500+ E-books