Answer 1

1. Use "age = gets.to_i". Whithout it, "age" is interpreted as a string, not an integer.
2. No human's age can be both less than 1 and greater than 5. Use "elsif x >= 1 && x <= 5". Same goes for your second elsif condition.
3. Answering your question, "elsif x >= 20 && x <= 25" does the job.