Odd One Out: Identifying the Composite Number
The question requires identifying the number that does not share a common property with the rest of the numbers in the set {19, 37, 21, 17, 23, 29, 31, 11}. We need to analyze the properties of each number.
Number Properties Analysis
- 19: Prime number (only divisible by 1 and 19).
- 37: Prime number (only divisible by 1 and 37).
- 21: Composite number (divisible by 1, 3, 7, and 21).
- 17: Prime number (only divisible by 1 and 17).
- 23: Prime number (only divisible by 1 and 23).
- 29: Prime number (only divisible by 1 and 29).
- 31: Prime number (only divisible by 1 and 31).
- 11: Prime number (only divisible by 1 and 11).
Conclusion
All the numbers in the given set are prime numbers, except for the number 21, which is a composite number. Therefore, 21 is the odd one out.
Important Questions from Number System
Consider the following statements :
1. (25)! + 1 is divisible by 26
2. (6)! + 1 is divisible by 7
Which of the above statements is/are correct ?
If the sum S is divided by 8, what is the remainder ?
If the sum S is divided by 60, what is the remainder ?
What is the Highest Common Factor of 2 3× 3 5and 3 3× 5 2?
Four prime numbers are arranged in ascending order. The product of the first three numbers is 255 and that of the last three is 1955. The largest prime number is:
