Which one of the following is a prime number ?

551 > 22

All prime numbers less than 24 are : 2, 3, 5, 7, 11, 13, 17, 19, 23.

119 is divisible by 7; 187 is divisible by 11; 247 is divisible by 13 and 551 is divisible by 19.

So, none of the given numbers is prime.

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In a family, there are six members A, B, C, D, E and F. A and B are a married couple, A being the male member. D is the only son of C, who is the brother of A. E is the sister of D. B is the daughter-in-law of F, whose husband has died. How is E related to C?

Option (B)

A is a male and married to B. So, A is the husband and B is the wife. C is the brother of A. D is the son of C. E, who is the sister of D will be the daughter of C. B is the daughter-in-law of F whose husband has died means F is the mother of A. Clearly, E is the daughter of C.

In alphabet series, some alphabets are missing which are given in that order as one of the alternatives below it. Choose the correct alternative.

ccb _ c _ bbc _ b _ cc _ _ ccbb

The series is ccbb / ccbb / ccbb / ccbb / ccbb. Thus, the pattern ccbb is repeated

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In following questions, a sequence of groups of alphabets and numbers is provided with one term missing , Choose the missing term from options.

3F, 6G, 11I, 18L, ?

The letters in the first, second, third and fourth terms are respectively moved one, two three and four steps forward to obtain the letter in the subsequent terms. The two, three and four steps forward by the numbers is + 3, + 5, + 7, + 9.

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In following questions, one term in number series is incorrect.

Find out the incorrect number

1, 5, 5, 9, 7, 11, 11, 15, 12, 17

Find out the incorrect number

1, 5, 5, 9, 7, 11, 11, 15, 12, 17

The given sequence is a combination of two series:

I. 1, 5, 7, 11, 12 and

II. 5, 9, 11, 15, 17

The pattern in both I and II is + 4, + 2, + 4, + 2.

So, 12 is wrong and must be replaced by (11 + 2) i.e. 13..

In a family, there are six members A, B, C, D, E and F . A and B are married couple, A being a male member, D is the only son of C, who is the brother of A. E is a sister of D. B is a daughter in law of F, whose husband has died how is F related to C?

A is a male and married to B. So, A is a husband and B is a wife . C is the brother of A. D is a son of C. E, who is the sister of D will be the daughter of C. B is a daughter in law of F whose husband has died means F is the mother of A. F is a the mother of A and C is the brother of A. So, F is the mother of C..

A can complete a work in 20 days. B can complete the same task in 15 days. B worked for 10 days and left the job. In how many days A alone can complete the work?

B:s 10 days work=(1/15)*10

=2/3

Remaining work=(1-2/3)=1/3

Now,1/20 work is done by A in 1 day.

Hence ,1/3 work is done by A in (20*1/3)=6.6

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