Explanation

The pattern is: ×2 + 1

6 × 2 + 1 = 13

13 × 2 + 1 = 27

27 × 2 + 1 = 55

55 × 2 + 1 = 111

Last verified on 02-08-2026

Explanation

Given sequence: 4, 11, 7, 14, 10, 17, __, 20

Two alternating series are used:

First series: 4 → 7 → 10 → 13 (+3 each time)

Second series: 11 → 14 → 17 → 20 (+3 each time)

Missing number: 13

Explanation

Look at how much it increases each time:

Term 1: x  

Term 2: x + 6 → increased by 6  

Term 3: x + 18 → increased by 12  

Pattern of increases: 6, 12, ...  

It goes up by 6 each time. So next increase = 18

Term 4 = Term 3 + 18 = (x + 18) + 18 = x + 36

If we take x = 18, then the terms are 18, 24, 36, 54

Last verified on 05-09-2026

Explanation

1, 8, 27, 64, 125, 216, 343, and 512

1^3 = 1

2^3 = 8

3^3 = 27

4^3 = 64

5^3 = 125

6^3 = 216

7^3 = 343

8^3 = 512

Last verified on 05-09-2026

Explanation

The pattern in the series appears to be alternating between adding and subtracting.

27 + 5 = 32

32 - 2 = 30

30 + 5 = 35

35 - 2 = 33

33 + 5 = 38

Last verified on 05-09-2026