**Sol : **In this kind of questions we find the work force required to complete the work in 1 day (or given unit of time) then we equate the work force to find the relationship between the efficiencies (or work rate) between the different workers.

Therefore 6B+8G = 6 days

6(6B+8G)= 1 day (inversely proportional)

36B+48G =1 ( by unitary method)

Again 14B+10G = 4days

56B+40G =1

so, here it is clear that either we employ 36B and 48G to finish the work in 1 day or 56B and 40G to finish the same job in 1 day. thus , we can say

36B+48G = 56B+40G

20B = 8G

G= 2.5B

Thus a Girl is 2.5 times as efficient as a boy.

Now, since 36B+48G = 1

36B+48 (2.5 B)=1

156B=1

i.e., to finish the job in 1 day 156 boys are required or the amount of work is 156 boys-days

Again 1G+1B=2.5B+1B=3.5B

Now, since 156 boys can finish the job in 1 day

so 1 boy can finish the job in 1 156 days

3.5 boys can finish the job in = days.

A) 8 hrs 45 min | B) 8 hrs 42 min |

C) 8 hrs | D) 8 hrs 34 min |

Explanation:

Number of pages typed by Adam in 1 hour = = 6

Number of pages typed by Smith in 1 hour = = 8

Number of pages typed by both in 1 hour = (6 + 8) = 14

Time taken by both to type 110 pages = (120 * 1/14) = 8 = 8 hrs 34 min.

A) 24.5 days | B) 26.6 days |

C) 25 days | D) 20 days |

Explanation:

Arun has completed rd of the work in 8 days

Then he can complete the total work in

---- 8

1 ---- ?

= 24 days

But given Akhil is only 60% as efficient as Arun

Akhil =

Akhil can complete the total work in 40 days

Now, remaining 2/3rd of work can be completed in

1 ------ 40

------ ? 26.66 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) 10 days | B) 15 days |

C) 20 days | D) 5 days |

Explanation:

After 10 days, the remaining food would be sufficient for the 1000 students for 20 more days

If 1000 more students are added, it shall be sufficient for only 10 days (as the no. of students is doubled, the days are halved).

A) 4:5 | B) 3:4 |

C) 4:3 | D) 2:3 |

Explanation:

(2018) men can complete the work in in one day.

one man's one day work =

(1815) women can complete the work in 1 day

1 woman's one day work =

So, required ratio = = 4:3