A can do a work in 10 days and B can do the same work in 15 days. If they work on it together for 4 days, then the fraction of the work that is left is:
Answer & explanation
Correct answer: option 4
A = 10 days,
B = 15 days,
⇒ A+ B worked for 4 days = (3 + 2) x 4 = 5 x 4 = 20 units,
⇒ Remaining work = 30 - 20 = 10 units,
⇒ Fraction of work left = \(\frac{10}{30}\) = \(\frac{1}{3}\)