A) A | B) B |

C) C | D) can't be determined |

Explanation:

A + B= 70%

B + C =50%

B= 20% A= 50% and C=30%

Hence A is most efficient

A) 7 hrs | B) 6 hrs 10 min |

C) 5 hrs 25min | D) 8 hrs 15 min |

Explanation:

A can write in 1hour = 32/6 pages

similarly

B in 1 hour = 40/5 pages

Together (A+B) in 1 hour = 32/6 + 40/5 = 40/3

so,

A+B write 40/3 pages in 1 hour

A+B write 110 pages in (3/40) x 110 Hours = 8 hours 15 min.

A) 6 days | B) 12 days |

C) 4 days | D) 9 days |

Explanation:

K's 1 day's salary = 1/10

L's 1 day's salary = 1/15

Together their 1 day's salary = 1/10 + 1/15

= 3/30 + 2/30

= 5/30

= 1/6

So the money will be

enough for paying them both for 6 days.

A) 17 men | B) 14 men |

C) 13 men | D) 16 men |

Explanation:

M x T / W = Constant

where, M= Men (no. of men)

T= Time taken

W= Work load

So, here we apply

M1 x T1/ W1 = M2 x T2 / W2

Given that, M1 = 4 men, T1 = 7 hours ; T2 = 2 hours, we have to find M2 =?

Note that here, W1 = W2 = 1 road, ie. equal work load.

Clearly, substituting in the above equation we get, M2 = 14 men.

A) 45 metric tonnes | B) 47 metric tonnes |

C) 55 metric tonnes | D) 34 metric tonnes |

Explanation:

2 engines of former type for one hour consumes 2x24/(6x8) = 1 metric ton

i.e. 3 engines of latter type consumes 1 ton for one hour

hence 9 engines consumes 3 tons for one hour

for 15 hours it is 15 x 3 = 45 metric tonnes.

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.