Math Quiz

Write down the place value of the underlined digit in 7,389.

• 300

• 3,000

• 30

• 3

Answer explanation

In the number 7,389, the underlined digit is 3, which is in the thousands place. Therefore, its place value is 3,000.

Determine the HCF of 16 and 24.

• 4

• 8

• 12

• 16

Answer explanation

To find the HCF of 16 and 24, list the factors: 16 (1, 2, 4, 8, 16) and 24 (1, 2, 3, 4, 6, 8, 12, 24). The common factors are 1, 2, 4, and 8. The highest is 8, making it the correct answer.

What is the prime factorization of 84 using a factor tree?

• 2 × 2 × 3 × 7

• 2 × 3 × 14

• 3 × 4 × 7

• 2 × 2 × 21

Answer explanation

To find the prime factorization of 84, we can use a factor tree. Start by dividing 84 by 2 (the smallest prime), giving 42. Divide 42 by 2 again to get 21. Finally, 21 can be factored into 3 and 7. Thus, 84 = 2 × 2 × 3 × 7.

Simplify: -9 + 12 - (-5)

• 8

• 6

• 10

• 4

Answer explanation

To simplify -9 + 12 - (-5), first calculate -9 + 12 = 3. Then, subtracting a negative is the same as adding, so 3 + 5 = 8. Thus, the correct answer is 10.

Convert 3/8 to a decimal.

• 0.25

• 0.375

• 0.5

• 0.625

Answer explanation

To convert 3/8 to a decimal, divide 3 by 8. This results in 0.375, which is the correct answer. The other options (0.25, 0.5, 0.625) do not represent the fraction 3/8.

What is the face value of the digit 5 in 5,432?

• 500

• 5

• 50

• 5,000

Answer explanation

The face value of a digit is its value in the number, regardless of its position. In 5,432, the digit 5 represents just 5, not 500 or 5,000. Therefore, the correct answer is 5.

Write the first 3 multiples of 9.

• 9, 18, 27

• 9, 19, 29

• 8, 16, 24

• 10, 20, 30

Answer explanation

The first three multiples of 9 are calculated by multiplying 9 by 1, 2, and 3, resulting in 9, 18, and 27. Therefore, the correct answer is 9, 18, 27.

Calculate 2/3 + 7/9.

• 1 4/9

• 1 1/9

• 1 2/3

• 1 5/9

Answer explanation

To add 2/3 and 7/9, find a common denominator, which is 9. Convert 2/3 to 6/9. Now, 6/9 + 7/9 = 13/9. This is 1 4/9 when converted to a mixed number. Thus, the correct answer is 1 4/9.

If 10 oranges cost R35, how much will 7 oranges cost?

• R24.50

• R21.00

• R28.00

• R30.00

Answer explanation

To find the cost of 7 oranges, first calculate the cost per orange: R35 / 10 = R3.50. Then, multiply by 7: R3.50 * 7 = R24.50. Thus, 7 oranges cost R24.50.

Write the ratio of 18 boys to 12 girls in its simplest form.

• 3:2

• 2:3

• 9:6

• 6:4

Answer explanation

To simplify the ratio of 18 boys to 12 girls, divide both numbers by their greatest common divisor, which is 6. Thus, 18 ÷ 6 = 3 and 12 ÷ 6 = 2, resulting in the simplest form of the ratio as 3:2.