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]

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

60 men could complete a piece of work in 250 days. They worked together for 200 days. After that work had to be stopped for 10 days due to bad weather. How many more men should be engaged to complete the work in time ?

• 1] 10
• 2] 15
• 3] 18
• 4] 20

A, B and C can do a piece of work in 36, 54 and 72 days respectively. They started the work but A left 8 days before the completion of the work while B left 12 days before completion. The number of days for which C worked is

• 1]

  4

• 2]

  8

• 3]

  12

• 4]

  24

A road of 5 m length will be constructed in 100 days. So, 280 workers were employed. But after 80 days it was found that only \({ \text{3}}\frac{1}{2}\) km road was completed. Now, how many more people were needed to finish the work in the specified time?

• 1] 480
• 2] 80
• 3] 200
• 4] 100

P is thrice as good a workman as Q and together they finish a piece of work in 24 days. The number of days taken by P alone to finish the work is:

• 1]

  25 days

• 2]

  22 days

• 3]

  32 days

• 4]

  34 days

Two pipes A and B can fill a tank in 36 min. and 45 min. respectively. Another pipe C can empty the tank in 30 min. First A and B are opened. After 7 minutes, C is also opened. The tank filled up in:

• 1] 39 min.
• 2] 46 min
• 3] 40 min.
• 4] 45 min.

A, B and C can separately do a work in 12, 15 and 20 days respectively. They started to work together but C left after 2 days. The remaining work will be finished in = ?

• 1] 4 days
• 2] 5 days
• 3] 6 days
• 4] 15 days

A, B and C can complete a piece of work in 10, 12 and 15 days respectively. A left the work 5 days before the work was completed and B left 2 days after A had left. Number of days required to complete the whole work was ?

• 1] 5 days
• 2] 6 days
• 3] 8 days
• 4] 7 days

A man can do a piece of work in 30 hours. If he works with his son then the same piece of work is finished in 20 hours. If the son works alone then he do the work in ?

• 1] 60 hours
• 2] 50 hours
• 3] 25 hours
• 4] 10 hours

A and B can together finish a piece of work in 30 days. They worked on it 20 days and then B left. The remaining work was done by A alone in 20 days. A alone can finish the work in = ?

• 1] 60 days
• 2] 54 days
• 3] 48 days
• 4] 50 days