Math Quiz for Class 8 Students

1. What is the volume of a cube with side length 3 cm?

9 cm cubed

18 cm cubed

27 cm cubed

24 cm cubed

Calculating the volume of a cube entails cubing the length of one of its sides, which is mathematically represented as side x side x side. In this instance, the cube possesses a side length of 3 cm. Therefore, its volume is computed as 3 cm x 3 cm x 3 cm, resulting in a volume of 27 cm³.

Explanation

Calculating the volume of a cube entails cubing the length of one of its sides, which is mathematically represented as side x side x side. In this instance, the cube possesses a side length of 3 cm. Therefore, its volume is computed as 3 cm x 3 cm x 3 cm, resulting in a volume of 27 cm³.

2. Solve for x if 4x + 5 = 21.

4

3

5

2

To determine the value of 'x' in the equation 4x + 5 = 21, we must isolate 'x' by employing inverse operations. Initially, we subtract 5 from both sides of the equation, resulting in 4x = 16. To fully isolate 'x', we divide both sides of the equation by 4, which ultimately yields x = 4.

Explanation

To determine the value of 'x' in the equation 4x + 5 = 21, we must isolate 'x' by employing inverse operations. Initially, we subtract 5 from both sides of the equation, resulting in 4x = 16. To fully isolate 'x', we divide both sides of the equation by 4, which ultimately yields x = 4.

3. Simplify: (-3)^2

6

-9

9

-6

When a negative number is squared, the result is always positive. This is because squaring a number involves multiplying it by itself. In the case of (-3)², we have (-3) x (-3). The multiplication of two negative numbers always yields a positive product, hence (-3)² = 9.

Explanation

When a negative number is squared, the result is always positive. This is because squaring a number involves multiplying it by itself. In the case of (-3)², we have (-3) x (-3). The multiplication of two negative numbers always yields a positive product, hence (-3)² = 9.

4. Convert 1500 milliliters to liters.

1.5 liters

15 liters

0.15 liters

150 liters

Within the metric system, units are interrelated by powers of 10. Specifically, 1 liter (L) is composed of 1000 milliliters (ml). Consequently, converting a quantity from milliliters to liters necessitates dividing the number of milliliters by 1000. In this case, 1500 ml ÷ 1000 yields 1.5 L.

Explanation

Within the metric system, units are interrelated by powers of 10. Specifically, 1 liter (L) is composed of 1000 milliliters (ml). Consequently, converting a quantity from milliliters to liters necessitates dividing the number of milliliters by 1000. In this case, 1500 ml ÷ 1000 yields 1.5 L.

5. What is the probability of rolling an even number on a standard six-sided die?

1/2

1/3

2/3

1/6

The concept of probability is defined as the ratio of favorable outcomes to the total number of possible outcomes. A standard six-sided die features three faces displaying even numbers (2, 4, and 6) out of a total of six faces. Therefore, the probability of obtaining an even number upon rolling the die is 3/6, which can be simplified to 1/2.

Explanation

The concept of probability is defined as the ratio of favorable outcomes to the total number of possible outcomes. A standard six-sided die features three faces displaying even numbers (2, 4, and 6) out of a total of six faces. Therefore, the probability of obtaining an even number upon rolling the die is 3/6, which can be simplified to 1/2.

6. If the circumference of a circle is 31.4 cm, what is its diameter? (Use pi approximately equal to 3.14)

10 cm

5 cm

20 cm

15 cm

The relationship between a circle's circumference (C) and its diameter (d) is given by the formula C = πd, where π (pi) is a mathematical constant approximately equal to 3.14. To determine the diameter when the circumference is known, we rearrange the formula to d = C/π. Substituting the given circumference of 31.4 cm, we get d = 31.4 cm / 3.14 = 10 cm.

Explanation

The relationship between a circle's circumference (C) and its diameter (d) is given by the formula C = πd, where π (pi) is a mathematical constant approximately equal to 3.14. To determine the diameter when the circumference is known, we rearrange the formula to d = C/π. Substituting the given circumference of 31.4 cm, we get d = 31.4 cm / 3.14 = 10 cm.

7. Which term describes a polygon with all sides and angles equal?

Regular

Irregular

Equilateral

Quadrilateral

In geometry, a polygon with all sides and all angles equal is specifically termed a "regular polygon." It's important to differentiate this from "equilateral," which refers only to the equality of sides. A square, for example, is a regular polygon because it has both equal sides and equal angles, while a rhombus, with equal sides but potentially unequal angles, is not.

Explanation

In geometry, a polygon with all sides and all angles equal is specifically termed a "regular polygon." It's important to differentiate this from "equilateral," which refers only to the equality of sides. A square, for example, is a regular polygon because it has both equal sides and equal angles, while a rhombus, with equal sides but potentially unequal angles, is not.

8. What is the prime factorization of 60?

2^2 x 3 x 5

2 x 3 x 5

2^2 x 5

3 x 5

Prime factorization is the process of expressing a number as the product of its prime factors. To find the prime factorization of 60, we start by dividing it by the smallest prime number, 2. This gives us 30. We can divide by 2 again to get 15. 15 is divisible by 3, resulting in 5, which is a prime number. Therefore, the prime factorization of 60 is 2 x 2 x 3 x 5, which can be written more compactly as 2² x 3 x 5.

Explanation

Prime factorization is the process of expressing a number as the product of its prime factors. To find the prime factorization of 60, we start by dividing it by the smallest prime number, 2. This gives us 30. We can divide by 2 again to get 15. 15 is divisible by 3, resulting in 5, which is a prime number. Therefore, the prime factorization of 60 is 2 x 2 x 3 x 5, which can be written more compactly as 2² x 3 x 5.

9. Calculate the area of a triangle with a base of 10 cm and a height of 14 cm.

140 cm squared

70 cm squared

50 cm squared

120 cm squared

Calculating the area of a triangle involves utilizing the formula: (1/2) x base x height. In this specific scenario, the triangle's base measures 10 cm and its height is 14 cm. Substituting these values into the formula, we obtain (1/2) x 10 cm x 14 cm. Simplifying this expression, we arrive at 5 cm x 14 cm, which ultimately yields 70 cm² as the area of the triangle.

Explanation

Calculating the area of a triangle involves utilizing the formula: (1/2) x base x height. In this specific scenario, the triangle's base measures 10 cm and its height is 14 cm. Substituting these values into the formula, we obtain (1/2) x 10 cm x 14 cm. Simplifying this expression, we arrive at 5 cm x 14 cm, which ultimately yields 70 cm² as the area of the triangle.

10. What is the result of 15 divided by 3 times 2 plus 5?

20

25

15

10

To solve the expression 15 ÷ 3 x 2 + 5, we must follow the order of operations, often remembered by the acronym PEMDAS (Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right)). In this case, we first perform the division: 15 ÷ 3 = 5. Next, we proceed with the multiplication: 5 x 2 = 10. Finally, we add 5 to get the result: 10 + 5 = 15.

Explanation

To solve the expression 15 ÷ 3 x 2 + 5, we must follow the order of operations, often remembered by the acronym PEMDAS (Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right)). In this case, we first perform the division: 15 ÷ 3 = 5. Next, we proceed with the multiplication: 5 x 2 = 10. Finally, we add 5 to get the result: 10 + 5 = 15.

Math Quiz For Class 8 Students