The series is: 1, 3, 6, 10, 15. What is the next number?
Question 1
Q1. The series is: 1, 3, 6, 10, 15. What is the next number?
Answer: 21
Explanation: The pattern is formed by adding consecutive integers: +2, +3, +4, +5, +6. So, 15 + 6 = 21