CAT (QA) PYQs

Bob can finish a job in $40$ days, if he works alone. Alex is twice as fast as Bob and thrice as fast as Cole in the same job. Suppose Alex and Bob work together on the first day, Bob and Cole work together on the second day, Cole and Alex work together on the third day, and then, they continue the work by repeating this three- day roster, with Alex and Bob working together on the fourth day, and so on. Then, the total number of days Alex would have worked when the job gets finished, is

A contractor agreed to construct a $6$ km road in $200$ days. He employed $140$ persons for the work. After $60$ days, he realized that only $1.5$ km road has been completed. How many additional people would he need to employ in order to finish the work exactly on time?

Anil can paint a house in $12$ days while Barun can paint it in $16$ days. Anil, Barun, and Chandu undertake to paint the house for ₹ $24000$ and the three of them together complete the painting in $6$ days. If Chandu is paid in proportion to the work done by him, then the amount in INR received by him is