1 View

Question : A, B, and C can complete a work in 10, 12 and 15 days respectively. A left the work 5 days before the work was completed and B left 2 days after A had left. Number of days required to complete the whole work is:

Option 1: $8\frac{2}{3}$

Option 2: $6\frac{2}{3}$

Option 3: $7$

Option 4: $6$


Team Careers360 21st Jan, 2024
Answer (1)
Team Careers360 22nd Jan, 2024

Correct Answer: $7$


Solution : Given: A, B, and C can complete a work in 10, 12, and 15 days respectively. A left the work 5 days before the work was completed and B left 2 days after A had left.
Let total work = LCM of 10, 12, and 15 = 60 units [Use: Efficiency = $\frac{\text{Total Work}}{\text{Time}}$]
So, A's efficiency = $\frac{60}{10}=6$
B's efficiency is = $\frac{60}{12}=5$
C's efficiency is = $\frac{60}{15}=4$
Let $n$ number of days required to complete the 60 units of work.
According to the question,
$6 \times(n-5) + 5 \times (n-3) + 4 n = 60$
⇒ $6n-30+5n-15+4n=60$
⇒ $15n = 105$
⇒ $n=7$
Hence, the correct answer is $7$.

How to crack SSC CHSL

Candidates can download this e-book to give a boost to thier preparation.

Download Now

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
GRE ® Registrations 2024
Apply
Apply for GRE® Test now & save 10% with ApplyShop Gift Card | World's most used Admission Test for Graduate & Professional Schools
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