Multiple choice

A series is given, with one/two term missing. Choose the correct alternative from the given ones that will complete the series. $-1, 0, 3, 8, 15, ?$

  1. $25$
  2. $23$
  3. $26$
  4. $24$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The pattern is n²-1 starting from n=0: 0²-1=-1, 1²-1=0, 2²-1=3, 3²-1=8, 4²-1=15. The next term is 5²-1=24. Alternatively, the differences increase by 2 each time: +1, +3, +5, +7, so next is +9 giving 24.