“What is the next number in the series: 1 1 2 6 24 ?”

"The series 1 1 2 6 24 represents factorials (1! 2! 3! 4! 5!) making the next number 6! = 120. This pattern illustrates the mathematical concept of factorials used in probability and combinatorics. Understanding the number 120 in this context highlights the application of factorials in advanced mathematics a key topic in algebra and statistics."