Algebra-1

Question Analysis
This question tests the student's ability to recognize irrational numbers based on their decimal expansion. The problem provides a specific example of a non-terminating, non-repeating decimal.

Key Concept Explanation
A number is irrational if its decimal expansion is non-terminating and non-repeating. The given number, 0.123456789101112131415..., continues indefinitely without any repeating pattern, making it an irrational number.

Step-by-step Solution
1. Examine the decimal expansion: 0.123456789101112131415...
2. Recognize that the digits continue in a ...