K and L undertake to do a piece of work for Rs 800 K alone can do it in 8 days while L alone ca...........

Quantitative Aptitude (CDS) Time and work

K and L undertake to do a piece of work for Rs. 800. K alone can do it in 8 days while L alone can do it in 10 days. With the help of M, they finish it in 4 days. What is the difference between the share of K and M?

Rs. 280

Rs. 300

Rs. 320

Rs. 350

Explanation:

M's 1 day's work = 1/4 - (1/8 +1/10)
= 1/40
K : L : M = Ratio of their 1 day's work = 1/8 : 1/10 : 1/40
= 5 : 4 : 1
K's share = Rs. (800×5/10) = Rs. 400
L's share = Rs. (800×4/10) = Rs. 320
M's share = Rs. (800×1/10) = Rs. 80
Difference between the share of K and M = 400 - 80
= Rs.320