1. Every natural number is:
Answer:
Explanation:
Natural numbers are a subset of real numbers. Thus, every natural number is a real number.
2. Which of the following is an irrational number?
Answer:
Explanation:
√2 cannot be expressed as a fraction of two integers, making it an irrational number.
3. Which of the following is NOT a property of real numbers?
Answer:
Explanation:
Multiplicative Inversion is not a property; it's a concept where each number has an inverse such that their product is 1.
4. The decimal expansion of a rational number:
Answer:
Explanation:
The decimal expansion of a rational number either terminates or becomes recurring.
5. Which number is NOT rational?
Answer:
Explanation:
√5 does not have an exact decimal representation and cannot be expressed as a quotient of two integers.
6. The smallest prime number is:
Answer:
Explanation:
2 is the smallest and only even prime number.
7. The HCF of two prime numbers is:
Answer:
Explanation:
Two distinct prime numbers do not have any common factors other than 1.
8. If a and b are real numbers, then a × b is:
Answer:
Explanation:
The product of two real numbers is always a real number.
9. An example of a non-terminating, non-recurring decimal is:
Answer:
Explanation:
3.141592… represents the irrational number π, which is non-terminating and non-recurring.
10. Which of the following is an example of a composite number?
Answer:
Explanation:
9 can be divided by 1, 3, and 9. Hence, it's a composite number.
11. Which of the following numbers lies between 0 and 1?
Answer:
Explanation:
√1/2 is equal to √0.5, which is between 0 and 1.
12. The value of (-1) × (-1) is:
Answer:
Explanation:
Negative multiplied by negative gives a positive number.
13. An integer that is not prime is called:
Answer:
Explanation:
A composite number has more than two distinct positive divisors.
14. The number 0 is:
Answer:
Explanation:
0 can be expressed as 0/1, making it a rational number.
15. Which of the following is an integer?
Answer:
Explanation:
√4 is equal to 2, which is an integer.
16. The LCM of 1 and any integer 'n' is:
Answer:
Explanation:
1 is a factor of every integer, so the LCM of 1 and any integer 'n' is 'n'.
17. Which of the following numbers is rational?
Answer:
Explanation:
0.75 can be expressed as 3/4, which is a ratio of two integers.
18. If x is an integer and y is a fraction, then x+y is:
Answer:
Explanation:
The sum of an integer and a fraction is a real number.
19. The product of two irrational numbers:
Answer:
Explanation:
For instance, the product of √2 and √2 is 2, which is rational.
20. The sum of two rational numbers is always:
Answer:
Explanation:
The sum of two rational numbers is always rational.