Between two book-ends in your study are displayed your five favourite puzzle books. If you decide to arrange the five books in every possible combination and moved just one book every minute, how long would it take you ?

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Question: Between two book-ends in your study are displayed your five favourite puzzle books. If you decide to arrange the five books in every possible combination and moved just one book every minute, how long would it take you ?
[A].

1 hour

[B].

2 hours

[C].

3 hours

[D].

4 hours

Answer: Option B

Explanation:

Clearly, number of ways of arranging 5 books = 5 ! = 5 x 4 x 3 x 2 x 1 = 120.

So, total time taken = 120 minutes = 2 hours.

Multistage compression of air as compared to single stage compression offers the advantage of

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Question: Multistage compression of air as compared to single stage compression offers the advantage of
[A].

power saving per unit weight of air delivered.

[B].

moisture elimination in the inter-stage cooler.

[C].

increased volumetric efficiency.

[D].

all (a), (b) & (c).

Answer: Option D

Explanation:

No answer description available for this question.

Mr. X, a mathematician, defines a number as ‘connected with 6 if it is divisible by 6 or if the sum of its digits is 6, or if 6 is one of the digits of the number. Other numbers are all ‘not connected with 6’. As per this definition, the number of integers from 1 to 60 (both inclusive) which are not connected with 6 is

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Question: Mr. X, a mathematician, defines a number as ‘connected with 6 if it is divisible by 6 or if the sum of its digits is 6, or if 6 is one of the digits of the number. Other numbers are all ‘not connected with 6’. As per this definition, the number of integers from 1 to 60 (both inclusive) which are not connected with 6 is
[A].

18

[B].

22

[C].

42

[D].

43

Answer: Option D

Explanation:

Numbers from 1 to 60, which are divisible by 6 are : 6,12,18, 24, 30, 36,42, 48, 54, 60.

There are 10 such numbers.

Numbers from 1 to 60, the sum of whose digits is 6 are : 6, 15, 24, 33, 42, 51, 60.

There are 7 such numbers of which 4 are common to the above ones. So, there are 3such uncommon numbers.

Numbers from 1 to 60, which have 6 as one of the digits are 6, 16, 26, 36, 46, 56, 60.

Clearly, there are 4 such uncommon numbers.

So, numbers ‘not connected with 6’ = 60 – (10 + 3 + 4) = 43.

‘End cooler’ or ‘after cooler’ is employed in air compressor mainly to

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Question: ‘End cooler’ or ‘after cooler’ is employed in air compressor mainly to
[A].

remove oil vapour or moisture from air.

[B].

cool the dry air before use.

[C].

reduce the volumetric capacity of receiver.

[D].

none of these.

Answer: Option A

Explanation:

No answer description available for this question.

Capacity & power requirement for an air compressor working at high altitude compared to sea-level will be

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Question: Capacity & power requirement for an air compressor working at high altitude compared to sea-level will be
[A].

more

[B].

less

[C].

same

[D].

either more or less; depends on the climatic conditions.

Answer: Option B

Explanation:

No answer description available for this question.