a) 18 days b) 22 ½ days c) 24 days d) 26 days
Basic Math MCQ 15 ( Work capability comparison )
MCQ 15: A is thrice as good as B in work. A is able to finish a job in 60 days less than B. They can finish the work in___________days if they work together.
A is thrice good than B — means A can do three times more work in one time duration !
i-e A can do three times more work in one day
1 day for A = 3W
But B takes 3 days for one work part
3 day for B = W
So we can see there is difference of 2 days !
With difference of 2 days B’ work finish in = 3 day
==> with difference of 1 day B’s work finish in = 3/2 days
==> with difference of 60 days B’s work finish in = 60 x 3/2 = 90 days
or with difference of 60 days ;
Work of B = 90 days
1 day (for B) = Work (of B) / 90 =W/90————-(1
As A can do three times more work than B;
1 day (for A) = 3x ( 1 day work of B)=3x W/90 =W/30 —————–(2
Adding eq 1 and 2
1 day ( for A + for B) = W/90+W/30= 4W/90
W = 90/4 days (for A+for B)
W = 22-1/2 days for ( A and B)
So It will take 22.5 days for both A and B to finish the work together !