Question : Two persons A and B working separately can sanitise a building in 6 hours and 10 hours, respectively. They work in stretches of one hour alternately. If A begins at 8 a.m., then when will the work be finished?
Option 1: $9\frac{1}{3}$ h
Option 2: $7\frac{1}{3}$ h
Option 3: $6\frac{1}{3}$ h
Option 4: $8\frac{1}{3}$ h
Latest: SSC CGL 2024 final Result Out | SSC CGL preparation tips to crack the exam
Don't Miss: SSC CGL Tier 1 Scorecard 2024 Released | SSC CGL complete guide
Suggested: Month-wise Current Affairs | Upcoming Government Exams
Correct Answer: $7\frac{1}{3}$ h
Solution : Person A can sanitise a building in 6 hrs. Person B can sanitise a building in 10 hrs. Total work = Efficiency$\times$Times Let the total work = LCM of 6 and 10 = 30 units Efficiency of A = $\frac{30}{6}$ = 5 units Efficiency of B = $\frac{30}{10}$ = 3 units According to the question, (5+3) = 8 units of work done in 2 hours So, in 6 hours work done = $8\times\frac{6}{2} = 24$ units Till 7th hour, work completed = 24 + 5 = 29 units Remaining work = 30 – 29 = 1 unit 1 unit of work is completed by B in $\frac{1}{3}\ \mathrm{hour}$ Total time is taken to complete the total work = $7\frac{1}{3}$ h Hence, the correct answer is $7\frac{1}{3}$ h.
Candidates can download this ebook to know all about SSC CGL.
Answer Key | Eligibility | Application | Selection Process | Preparation Tips | Result | Admit Card
Question : A and B working separately can complete a piece of work in 10 and 16 days, respectively. If they work for a day alternately, with A beginning the work, in how many day (s) will the work be completed?
Option 1: $10 \frac{1}{4}$
Option 2: $12 \frac{1}{4}$
Option 3: $1\frac{1}{4}$
Option 4: $\frac{1}{4}$
Question : A and B can do a piece of work in 5 days and 10 days, respectively. They began the work together but A left after some days and B finished the remaining work in 8 days. After how many days did A leave?
Option 1: $3\frac{1}{8}$
Option 2: $5\frac{1}{8}$
Option 3: $6\frac{1}{8}$
Option 4: $\frac{2}{3}$
Question : A, B, and C can do a piece of work in 30, 20, and 10 days respectively. A is assisted by B on one day and by C on the next day, alternately. How long would the work take to finish?
Option 1: $9 \frac{3}{8}$ days
Option 2: $4 \frac{8}{8}$ days
Option 3: $8 \frac{4}{13}$ days
Option 4: $3 \frac{9}{13}$ days
Question : If 90 men can do a certain job in 16 days, working 12 hours per day, then the part of that work which can be completed by 70 men in 24 days, working 8 hours per day is:
Option 1: $\frac{1}{3}$
Option 2: $\frac{2}{3}$
Option 3: $\frac{7}{9}$
Option 4: $\frac{5}{8}$
Question : A can do a piece of work in 6 days, working 8 hours a day, while B can do the same work in 4 days, working 10 hours a day. If the work has to be completed in 5 days, how many hours do they need to work together in a day?
Option 1: $4$
Option 2: $5\frac{4}{11}$
Option 3: $6\frac{4}{11}$
Option 4: $4\frac{4}{11}$
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile