Quiz Discussion

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 and B can together finish a work in 30 days. They worked together for 20 days and B left. After another 20 days, A finished the remaining work. In how many days A alone can finish the job ?

• 1] 40 days
• 2] 50 days
• 3] 54 days
• 4] 60 days

There are three boats A, B and C, working together they carry 60 people in each trip. One day an early morning A carried 50 people in few trips alone. When it stopped carrying the passengers B and C started carrying the people together. It took a total of 10 trips to carry 300 people by A, B and C. It is known that each day on an average 300 people cross the river using only one of the 3 boats A, B and C. How many trips it would take to A to carry 150 passengers alone?

• 1] 15
• 2] 30
• 3] 25
• 4] 10
• 5] None of these

A can finish a work in 24 days, B in 9 days and C in 12 days. B and C start the work but are forced to leave after 3 days. The remaining work was done by A in:

• 1]

  5 days

• 2]

  6 days

• 3]

  10 days

• 4]

  10* 1/2 days

Sakshi can do a piece of work in 20 days. Tanya is 25% more efficient than Sakshi. The number of days taken by Tanya to do the same piece of work is:

• 1]

  15

• 2]

  16

• 3]

  18

• 4]

  25

A can do a piece of work in 5 days less than the time taken by B to do it. If both of them together take \({ \text{11}}\frac{1}{9}\) days, then the time taken by B alone to do the same work (in days ) is?

• 1] 15 days
• 2] 20 days
• 3] 25 days
• 4] 30 days

A can lay railway track between two given stations in 16 days and B can do the same job in 12 days. With help of C, they did the job in 4 days only. Then, C alone can do the job in:

• 1]

  \(9\frac{1}{5}\) days

• 2]

  \(9\frac{2}{7}\) days

• 3]

  \(9\frac{3}{5}\) days

• 4]

  10

There is provision of food in fort for 1200 soldiers for 60 days. After 15 days, 200 soldiers leave the fort. Remaining food will last for how many days?

• 1] 56 days
• 2] 50 days
• 3] 54 days
• 4] 48 days

If 28 men complete \(\frac{7}{8}\) of a piece of work in a week, then the number of men, who must be engaged to get the remaining work completed in another week, is = ?

• 1] 5
• 2] 6
• 3] 4
• 4] 3

If A, B and C can complete a piece of work in 6 days. If A can work twice faster than B and thrice faster then C, than the number of days C alone can complete the work is ?

• 1] 44 days
• 2] 33 days
• 3] 22 days
• 4] 11 days