## 1. Which of the following is an irrational number?

### Answer:

### Explanation:

√2 cannot be expressed as a fraction, making it irrational.

## 2. Which number is both irrational and rational?

### Answer:

### Explanation:

A number cannot be both irrational and rational at the same time.

## 3. The decimal expansion of the rational number 3/8 is:

### Answer:

### Explanation:

Dividing 3 by 8 gives 0.375.

## 4. Which of the following is not a rational number?

### Answer:

### Explanation:

π (Pi) is an irrational number.

## 5. The value of √144 is:

### Answer:

### Explanation:

The square root of 144 is 12.

## 6. Which number system includes all other number systems?

### Answer:

### Explanation:

Real numbers include rational, irrational, integers, and natural numbers.

## 7. Which of the following is a terminating decimal?

### Answer:

### Explanation:

7 divided by 8 gives 0.875, which is terminating.

## 8. The decimal expansion of 1/7 is:

### Answer:

### Explanation:

1 divided by 7 results in a repeating decimal of 0.142857…

## 9. Every natural number is also a:

### Answer:

### Explanation:

All natural numbers are whole numbers and integers.

## 10. Which of the following is not a whole number?

### Answer:

### Explanation:

Whole numbers start from 0 and include all positive integers.

## 11. The value of -√49 is:

### Answer:

### Explanation:

The square root of 49 is 7. With the negative sign, it's -7.

## 12. What type of decimal expansion does the number 5/11 have?

### Answer:

### Explanation:

5/11 is 0.454545…

## 13. The product of a rational and an irrational number is:

### Answer:

### Explanation:

If the rational number is zero, the product is rational (0). Otherwise, it's irrational.

## 14. Which of these numbers is closest to the value of π?

### Answer:

### Explanation:

π is approximately 3.14159…

## 15. If a number is irrational, its square:

### Answer:

### Explanation:

For instance, (√2)^2 = 2, which is rational.

## 16. The smallest natural number is:

### Answer:

### Explanation:

Natural numbers start from 1.

## 17. Which of the following is an integer?

### Answer:

### Explanation:

-7 is a whole number and thus an integer.

## 18. Which number is not considered a real number?

### Answer:

### Explanation:

Imaginary numbers, like the square root of -1, are not real numbers.

## 19. Which of these is a property of rational numbers?

### Answer:

### Explanation:

Rational numbers can be expressed as a ratio of two integers.

## 20. The sum of two irrational numbers:

### Answer:

### Explanation:

For example, √2 + (-√2) = 0, which is rational.