Quiz Discussion

18 men or 36 boys working 6 hours a day can plough a field in 24 days. In how many days will 24 men and 24 boys working 9 hours a day plough the same field ?

• 1] 9 days
• 2] 10 days
• 3] 6 days
• 4] 8 days

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?

• 1] 12 min
• 2] 16 min
• 3] 18 min
• 4] 15 min
• 5] None of these

A and B can together do a piece of work it in 6 days and A alone can do it in 9 days. The number of days B will take to do it alone is ?

• 1] 18 days
• 2] 24 days
• 3] 9 days
• 4] 12 days

Three friends Anne, Bob and Chris work together to do a certain job. Time it takes them to do the work together to do a certain job. The it takes them to do the work together is 6 hours less than Anne would have take alone, 1 hour less than Bob would have taken alone and half the time Chris would have taken working alone text. How long did it take them to complete the job, working together ?

• 1] 20 minutes
• 2] 30 minutes
• 3] 40 minutes
• 4] 50 minutes

A, B and C can do a piece of work in 20, 30 and 60 days respectively. In how many days can A do the work if he is assisted by B and C on every third day?

• 1] 12 days
• 2] 15 days
• 3] 16 days
• 4] 18 days

A single reservoir supplies the petrol to the whole city, while the reservoir is fed by a single pipeline filling the reservoir with the stream of uniform volume. When the reservoir is full and if 40, 000 litres of petrol is used daily, the supply fails in 90 days. If 32, 000 litres of petrol used daily, it fails in 60 days. How much petrol can be used daily without the supply ever failing?

• 1] 64000 litres
• 2] 56000 litres
• 3] 60000 litres
• 4] 78000 litres
• 5] None of these

If m men can do a work in r days, then the number of days taken by (m + n) men to do it is :

• 1]

  \(\frac{{{ \text{m}} + { \text{n}}}}{{{ \text{mn}}}}\)

• 2]

  \(\frac{{{ \text{m}} + { \text{n}}}}{{{ \text{mr}}}}\)

• 3]

  \(\frac{{{ \text{mr}}}}{{{ \text{m}} + { \text{n}}}}\)

• 4]

  \(\frac{{{ \text{r}}\left( {{ \text{m}} + { \text{n}}} \right)}}{{{ \text{mn}}}}\)

A man, a woman and a boy can do a piece of work in 6, 9 and 18 days respectively. How many boys must assist one man and one woman to do the work in 1 day ?

• 1] 5
• 2] 6
• 3] 9
• 4] 13

12 men can do a piece of work in 24 days. How many days are needed to complete the work, if 8 men do this work ?

• 1] 28 days
• 2] 36 days
• 3] 48 days
• 4] 52 days

A can do a work in 15 days and B in 20 days. If they work on it together for 4 days, then the fraction of the work that is left is :

• 1]

  \(\frac{1}{4}\)

• 2]

  \(\frac{1}{{10}}\)

• 3]

  \(\frac{7}{{15}}\)

• 4]

  \(\frac{8}{{15}}\)