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

_ abb _ _ bb _ a _ bbab _ ba

The series is babb / babb / babb / babb / babb / ba. Thus, the pattern babb is repeated..

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

aa _ aaa _ aaaa _ aaaa _ b

The series is aab / aaab / aaaab / aaaaab. Thus, the number of a`s is increasing by one in the successive sequence.

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

Find out the incorrect number

445, 221, 109, 46, 25, 11, 4

Find out the incorrect number

445, 221, 109, 46, 25, 11, 4

3 is subtracted from each number and the result is divided by 2 to obtain the next number of the series.

So , 46 is wrong and must be replaced by 109 - 3 / 2 i.e. 53..

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

cccbb _ aa _ cc _ bbbaa _ c

The series is cc bbb aaa / ccc bbb aaa / c. Thus, the pattern ccc bbb aaa is repeated..

The sum of even numbers between 1 and 31 is:

Let Sn = (2 + 4 + 6 + ... + 30). This is an A.P. in which a = 2, d = 2 and l = 30

Let the number of terms be n. Then,

a + (n - 1)d = 30

2 + (n - 1) x 2 = 30

n = 15.

Sn =n/2(a + l)=15/2x (2 + 30) = (15 x 16) = 240.

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If x and y are positive integers such that (3x + 7y) is a multiple of 11, then which of the following will be divisible by 11 ?

By hit and trial, we put x = 5 and y = 1 so that (3x + 7y) = (3 x 5 + 7 x 1) = 22, which is divisible by 11.

(4x + 6y) = ( 4 x 5 + 6 x 1) = 26, which is not divisible by 11;

(x + y + 4 ) = (5 + 1 + 4) = 10, which is not divisible by 11;

(9x + 4y) = (9 x 5 + 4 x 1) = 49, which is not divisible by 11;

(4x - 9y) = (4 x 5 - 9 x 1) = 11, which is divisible by 11.

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In following alphabet series , one term missing as shown by question mark . Choose missing term from options.

A, Z, X, B, V, T, C, R, ?, ?

The first, fourth and seventh letters are in alphabetical order. So, tenth letter would be the letter after C i.e. D. Also, the second and third letters are alternate and in reverse order and so are the fifth and sixth letters and the eighth and ninth letters.

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