How many irrational numbers are there between 3 and 7?

How many integers are between and (not including and )?

3 candy bars and 4 bags of potato chips cost $7, and 3 candy bars and 2 bags of potato chips cost $5. What is the price of 1 bag of potato chips?

What is the average of all prime numbers in between 7 and 23 (not including 7 or 23)?

How many prime numbers are between 20 and 50?