Multiple choice

In the following number series one number is wrong. Find the wrong number.\n9 \quad 9 \quad 18 \quad 6 \quad 24 \quad 4 \quad 28.8

  1. $9$
  2. $18$
  3. $6$
  4. $24$
  5. $4$
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Pattern: 9 ÷ 1 = 9, 9 × 2 = 18, 18 ÷ 3 = 6, 6 × 4 = 24, 24 ÷ 6 = 4, 4 × 7.2 = 28.8. The pattern alternates division and multiplication: ÷1, ×2, ÷3, ×4, ÷5, ×6, ÷7. But after 24, we should have 24 ÷ 5 = 4.8, not 4. The number 4 is wrong. Then 4.8 × 6 = 28.8. The pattern works: alternating operations with consecutive integers.

Keep practicing — related questions