Two pipes A and B can fill a tank in 24 min. and 32 min. respectively. If both the pipes are opened simultaneously, after how much time B should be closed so that the tank is full in 18 minutes?

A completes 80% of a work in 20 days. Then B also joins and A and B together finish the remaining work in 3 days. How long does it need for B if he alone completes the work?

• [A] 36
• [B] 25
• [C] 37.5
• [D] 48
• [E] None of these

Two forest officials in their respective division were involved in the harvesting of tendu leave. One division had an average output of 21 tons from a hectares and other division, which had 12 hectares of land less, dedicated to tendu leaves, got 25 tons of tendu from a hectare. As a result, the second division harvested 300 tons of tendu leaves more than the first. How many tons of tendu leaves did the first division harvest.

• [A] 3150
• [B] 3450
• [C] 3500
• [D] 3600
• [E] None of these

At a Tech Pvt Ltd. there are some engineering students employed as trainee engineers, belong to two eminent institutions of India. One group belongs to IIT and another to NIT. Each student of IIT works for 10 hours a day till 60 days and each student of NIT works for 8 hours a day till 80 days on the two same project. The ratio of students of IIT and that of NIT is 4:5 respectively. Students of which institution is slower in work and by how much?

• [A] IITian is 20% less efficient
• [B] NITian is 33.33% less efficien
• [C] NIT is 25% less efficient
• [D] IIT is 33.33% less efficient
• [E] Cannot be determined

Three pipes A,B and C attached to a cistern. A can fill it in 10 min, B in 15 min, C is a waste pipe for emptying it. After opening both the pipes A and B, a man leaves the cistern and returns when the cistern should have been just full. Finding, however, that the waste pipe had left open, he closes it and the cistern now gets filled in 2 min. In how much time the pipe C, if opened alone, empty the full cistern?

• [A] 12 min
• [B] 16 min
• [C] 18 min
• [D] 15 min
• [E] None of these

A group of 12 men can do a piece of work in 14 days and other group of 12 women can do the same work in 21 days. They begin together but 3 days before the completion of work, man's group leaves off. The total number of days to complete the work is:

• [A] 65/4
• [B] 93/3
• [C] 51/5
• [D] 60