9 examiners can examine a certain number of answer books in 12 days by working 5 hours a day. How many hours in a day should 4 examiners work to examine twice the number of answer books in 30 days?

A and B can do a work in 10 days. B and C in 12 days while C and A in 15 days. How long would they take if all the three work together?

30 laborers, working 7 hours a day can finish a piece of work in 18 days. If the laborers work 6 hours a day, then the number of laborers to finish the same piece of work in 30 days, will be:

A, B and C can do a piece of work in 11 days, 20 days and 55 days respectively, working alone. How soon can the work be done if A is assisted by B and C on alternate days?

A tap can fill a tank in 16 minutes and another can empty it in 8 minutes. If the tank is already half full and both the tanks are opened together the tank will be:

A can do a piece of work in 10 days; B in 15 days. They work for 5 days. The rest of the work was finished by C in 2 days. If they get Rs. 1500 for the work, the daily wages of B and C are:

A and B can complete a work in 15 days and 10 days respectively. They started doing the work together but after 2 days B had to leave and A alone completed the remaining work. The whole work was completed in:

A 210m long train takes 6s to cross a man running at 9 kmph in a direction opposite to that of the train. What is the speed of the train? (in kmph)

X and Y can do a piece of work in 20 days and 12 days respectively. X started the work alone and then after 4 days Y joined him till the completion of the work. How long did the work last?

Mr. Ram is on tour and he has Rs 360 for his expenses. If he exceeds his tour by 4 days he must cut down daily expenses by Rs 3. The number of days of Mr. Ram's tour programme is