Basic Ability Test Basic Ability Number Series and Sequences 4

Question 1

What comes next in the alternating series: 1, 10, 2, 20, 3, 30, ___?

Accepted Answer

4

Answer

Odd positions form 1,2,3,… so the next odd-position term is 4.

Question 2

Find the missing term: 3, 9, 27, 81, ___?

Accepted Answer

243

Answer

Each term is multiplied by 3 (powers of 3), so 81 × 3 = 243.

Question 3

Complete the sequence: 17, 14, 11, 8, ___?

Accepted Answer

5

Answer

Each term decreases by 3, so 8 − 3 = 5.

Question 4

What is the next number? 2, 4, 8, 14, 22, ___?

Accepted Answer

32

Answer

Differences are 2, 4, 6, 8, 10 — increasing by 2 — so 22 + 10 = 32.

Question 5

Which value continues: 100, 50, 25, 12.5, ___?

Accepted Answer

6.25

Answer

Each term is halved, so 12.5 ÷ 2 = 6.25.

Basic Ability Test Practice Test