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) 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) 18 minutes | B) 19 minutes |

C) 22 minutes | D) 24 minutes |

Explanation:

Let the two conditioners be A and B

'A' cools at 40min

'B' at 45min

Together =(axb)/(a+b) = (45x40)/85 = 21.1764 = (approx) 22 min.

A) 120 | B) 240 |

C) 360 | D) 180 |

Explanation:

1/15 + 1/12 + 1/R = 1/6, we got R = 60 (it means R will take 60 days to complete the work alone)

so ratio of work done by P:Q:R = 1/15 : 1/12 : 1/60 = 5 : 4 : 1

so R share = (1/10)x1200 = 120.

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.

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.