issb intelligence MCQ #317

Next number: 1, 3, 6, 10, 15, ?

issb intelligence MCQ #317

  1. Question 1

    Q1. Next number: 1, 3, 6, 10, 15, ?

    • A) 18
    • B) 20
    • C) 21
    • D) 25

    Answer: 21

    Explanation: Triangular numbers add 2,3,4,5,6 so next is 21. Work each step carefully; ISSB math rewards accuracy under time pressure.