Efficiency of A is 50 more than B and B takes 21 days to complete a piece of work A started the work...........

Quantitative Aptitude ( CCS) Time and work

Efficiency of A is 50% more than B and B takes 21 days to complete a piece of work. A started the work alone and then B joined her 5 days before actual completion of the work. For how many days A worked alone?

6 days

4 1/2 days

5 2/3 days

7 days

छोटे Courses बड़े Results

Master Time and work

Prepare through Micro-courses

Try Now

Explanation:

Solution:
Efficiency (A : B) =150:100= 3 : 2 then days 2:3
B takes 21 days to do the work. Then A takes 14 days to do the work.
(3 === 21
2 === 14 days.)
Now A…….14 3unit
. B…….21 Lcm 42 2unit
then B joined with A and worked for 5days ==>5*5(3+2) = 25 unit
remaining (42-25)=17unit
then A did that 17 unit alone is 17/3==5 2/3 days.