Quantitative Aptitude - Arithmetic Ability Questions

From the beginning, the next term comes by adding prime numbers in a sequence of 2, 3, 5, 7, 9, 11, 13... to its previous term. But 165 will not be in the series as it must be replaced by 166 since 153+13 = 166.

1, 1 + 1² = 2, 2 + 2² = 6, 6 + 3² = 15, 15 + 4² = 31, 31 + 5² = 56, 56 + 6² = 92

Last number of given series must be 92 not 91.

The given number series follows the pattern that,

24×0 + 4  = 4  

4×1  + 9   = 13

13×2 + 16 = 42

42×3 + 25  = 151

151×4 + 36 =  640

Therefore, the odd number in the given series is 41

Let the numbers be 3x, 4x and 5x.

Then, their L.C.M. = 60x.

So, 60x = 2400 or x = 40.

 The numbers are (3 x 40), (4 x 40) and (5 x 40).

Hence, required H.C.F. = 40.

In the given series numbers are arranged following the rule,

55,44, 33, 22, 11

 Therefore, the missing number is 27.

The given series pattern follows

17       9       10       18.5       35       90

× 0.5 + 0.5,   × 1 + 1,   × 1.5 + 1.5,   × 2 + 2,   × 2.5 + 2.5

So here 

17x0.5 + 0.5 = 9

9x1 + 1 = 10

10x1.5 + 1.5 = 16.5

16.5x2 + 2 = 35

35x2.5 + 2.5 = 90

Here the odd man in the given series is 18.5

The Given number series 3, 6.5, 14, 29, 64, 136 follows a pattern that

3

3 x 2 + 0.5 = 6.5

6.5 x 2 + 1 = 14

14 x 2 + 2 = 30 ≠29

30 x 2 + 4 = 64

64 x 2 + 8 = 136

Thus the wrong number in the series is 29