DevSquare Quantitative Aptitude Number Series Questions

The given pattern is (Prime number - consecutive numbers
starting with 1).
1 = 2 – 1
1 = 3 – 2
2 = 5 – 3
3 = 7 – 4
6 = 11 – 5
7 = 13 – 6
10 = 17 – 7
11 = 19 – 8
14 = 23 – 9

This is an alternating addition series, with a random number, 21, interpolated as every third number. The addition series alternates between adding 3 and adding 4. The number 21 appears after each number arrived at by adding 3.

As we see the series 1,4,9,18......
we see that
2⁰ = 1
which is first term
2²+0 = 4
which is second term
2³+1 = 9
third term
2⁴+2 = 18
fourth term
2^5 +3 = 35
fifth term
2^6+4 = 68
sixth term
2^7+5 = 133
seventh term
2^8+6 = 262
eighth term so answer is 262

Since 2*3=6, 6*3=18, 18*3=54 so 54*3=162. Therefore next number is 162

The letters decrease by 1; the numbers are multiplied by 2.

Hence, E4

This is a simple addition series; each number is 3 more than the previous number.

Two series alternate here, with every third number following a different pattern. In the main series, 3 is added to each number to arrive at the next. In the alternating series, 5 is subtracted from each number to arrive at the next.

This simple addition series adds 4 to each number to arrive at the next.

There is a simple pattern in this sequence: it begins with 0
and then the prime numbers are added to consecutive
elements in ascending order

I.e., 2 is added to the first element

3 is added to second element

5 is added to third element and so on.

So, 0+2 = 2

2+ 3 = 5

5+ 5 = 10

10+ 7 = 17

17+ 11 = 28

28+ 13 = 41

( Sum of two previous digits + 1 )= Next digit in series.