# Time and Work Questions

A) 17 + 4/7 days | B) 13 + 1/3 days |

C) 15 + 3/2 days | D) 16 days |

Explanation:

C alone can finish the work in 40 days.

As given C does half as much work as A and B together

=> (A + B) can do it in 20 days

(A + B)s 1 days wok = 1/20.

A's 1 days work : B's 1 days Work = 1/2 : 1 = 1:2(given)

A's 1 day’s work = (1/20) x (1/3) = (1/60) [Divide 1/20 in the raio 1:2]

B's 1 days work = (1/20) x (2/3) = 1/30

(A+B+C)'s 1 day's work = (1/60) + (1/30) + (1/40) = 9/120 = 3/40

All the three together will finish it in 40/3 = 13 and 1/3 days.

A) 50 days | B) 48 days |

C) 47.5 days | D) 49 days |

Explanation:

50 men can build a tank in 40 days

Assume 1 man does 1 unit of work in 1 day

Then the total work is 50×40 = 2000 units

50 men work in the first 10 days and completes 50×10 = 500 units of work

45 men work in the next 10 days and completes 45×10 = 450 units of work

40 men work in the next 10 days and completes 40×10 = 400 units of work

35 men work in the next 10 days and completes 35×10 = 350 units of work

So far 500 + 450 + 400 + 350 = 1700 units of work is completed and

remaining work is 2000 - 1700 = 300 units

30 men work in the next 10 days. In each day, they does 30 units of work.

Therefore, additional days required =

Thus, total 10+10+10+10+10 = 50 days required.

A) 30 days | B) 40 days |

C) 120 days | D) 80 days |

Explanation:

Given K=4L

K+L = 4L+L = 5L

These 5L people can complete the work in 24 days, which means L alone can do the work in

245=120 days.

Hence, K alone can do the work in = 30 days.

A) [7 + (215/345)] days | B) [6 + (11/215)] days |

C) [6 + (261/315)] days | D) [5 + (112/351)] days |

Explanation:

After day 1, A finishes 1/9 of the work.

After day 2, B finishes 1/7 more of the total work. (1/9) + (1/7) is finished.

After day 3, C finishes 1/5 more of total work. Total finished is 143/315.

So, after day 6, total work finished is 286/315.

Now remaining work = 315 - 286 = 29 /315

On day 7, A will work again

Work will be completed on day 7 when A is working. He must finish 29/315 of total remaining work.

Since he takes 9 days to finish the total task, he will need 261/315 of the day.

Total days required is 6 + (261/315) days.

A) 7 hrs | B) 7.5 hrs |

C) 8 hrs | D) 8.25 hrs |

Explanation:

Let there are L men

job requires LK man hours.

job completed in first 4 hrs = Lx4 = 4L

job completed in next 4 hrs = 4xL/2 = 2L

job completed in next 4 hrs = 4xL/4 = L

job completed in last 4 hrs = 4xL/8 = L/2

4L + 2L + L + L/2 = KL

K = 7+1/2 = 7.5 hours.