Which of the given statements is/are necessary/required to answer the question. Rashmi works for 4 days and leaves the work. In how many days can Rashmi alone can finish the remaining work? I-Rashmi and Sweta can complete the whole work in 80/9 days. II-When Rashmi left 25% work was done. III-Sweta is 20% less efficient than Rashmi.

Rashmi worked for 4 days when 25% work was done. So remaining work = 75%. Statement I: Rashmi + Sweta complete in 80/9 days, so combined rate = 9/80 per day. Statement III: Sweta's efficiency is 20% less than Rashmi, so Sweta's rate = 0.8 × Rashmi's rate. If Rashmi's rate = r, then r + 0.8r = 9/80, so 1.8r = 9/80, r = 1/16 per day. For 75% work at rate 1/16: days = (3/4)/(1/16) = 12 days. Statements II and III are sufficient. Alternatively: I+III gives Rashmi's rate = 1/16, and we know 4 days were worked. We need to know how much work is left (from II) to calculate remaining days. So 'II or (I and III)' are sufficient. Claimed answer E is correct.