Mensa IQ Test Mensa IQ Sequence Completion 3

Question 1

What comes next: 1, 4, 27, 256, ___?

Accepted Answer

3125

Answer

Each number is n^n: 1¹=1, 2²=4, 3³=27, 4⁴=256, 5⁵=3125. The base and exponent are the same number, increasing by 1 each time.

Question 2

Complete the sequence: 2, 6, 12, 20, 30, ___?

Accepted Answer

42

Answer

These numbers follow the pattern n(n+1): 1×2=2, 2×3=6, 3×4=12, 4×5=20, 5×6=30, 6×7=42. The differences are 4, 6, 8, 10, 12 — increasing by 2.

Question 3

What number comes next: 5, 10, 20, 40, 80, ___?

Accepted Answer

160

Answer

Each number is doubled: 5×2=10, 10×2=20, etc. The next term is 80×2=160. This is a geometric sequence where each term is multiplied by the common ratio of 2.

Question 4

Complete the sequence: 1, 1, 2, 6, 24, 120, ___?

Accepted Answer

720

Answer

These are factorials: 0!=1, 1!=1, 2!=2, 3!=6, 4!=24, 5!=120, 6!=720. Each term is multiplied by the next integer: 120×6=720.

Question 5

What comes next in the sequence: 2, 3, 5, 9, 17, ___?

Accepted Answer

33

Answer

Each term follows the rule: double the previous term and subtract 1. 2×2-1=3, 3×2-1=5, 5×2-1=9, 9×2-1=17, 17×2-1=33. Alternatively, differences double: 1, 2, 4, 8, 16.

Mensa Practice Test Practice Test

Mensa Practice Test Practice Test

Mensa IQ Test Mensa IQ Sequence Completion 3