Vietnam · Grade 7 · Practice Sheet 18

1. 1.

   Find the mean (average) of these numbers: 96, 65, 34, 19.

   Formula:Arithmetic Mean

   $\bar{x} = \dfrac{\sum x}{n}$

   View formula →
2. 2.

   A circle has a radius of 16 cm. Find its area. (Use π ≈ 3.14159)

   Formula:Area of a Circle

   $A = \pi r^2$

   View formula →
3. 3.

   VND 3,900 is invested at 10% simple interest per year for 4 years. Find the interest earned.

   Formula:Simple Interest

   $I = \dfrac{P \times r \times t}{100}$

   View formula →
4. 4.

   A bag has 30 equally likely marbles, of which 14 are red. Find the probability of drawing a red marble (to 3 d.p.).

   Formula:Simple Probability

   $P(E) = \dfrac{\text{favourable}}{\text{total}}$

   View formula →
5. 5.

   Find the mean (average) of these numbers: 59, 45, 46, 46, 67, 20.

   Formula:Arithmetic Mean

   $\bar{x} = \dfrac{\sum x}{n}$

   View formula →
6. 6.

   Convert 7.62 kilometres into metres.

   Formula:Metric Length Conversion

   $1\,\text{km} = 1000\,\text{m}$

   View formula →
7. 7.

   What is 20% of 130?

   Formula:Percentage of a Quantity

   $\text{result} = \dfrac{p}{100} \times N$

   View formula →
8. 8.

   One item costs VND 2.39. Find the total cost of 3 items.

   Formula:Total Cost

   $\text{total} = \text{price} \times \text{quantity}$

   View formula →
9. 9.

   A value changes from 134 to 191. Find the percentage change (to 2 d.p.).

   Formula:Percentage Change

   $\%\,\text{change} = \dfrac{\text{new} - \text{old}}{\text{old}} \times 100$

   View formula →
10. 10.

    Find the circumference of a circle whose radius is 16 m. (Use π ≈ 3.14159)

    Formula:Circumference of a Circle

    $C = 2\pi r$

    View formula →
11. 11.

    Solve for x: 4x + 6 = 34.

    Formula:Solving a Linear Equation

    $x = \dfrac{c - b}{a}$

    View formula →
12. 12.

    A triangle has a base of 28 cm and a height of 26 cm. Find its area.

    Formula:Area of a Triangle

    $A = \tfrac{1}{2} b h$

    View formula →
13. 13.

    VND 198 is shared in the ratio 3 : 3. Find each share.

    Formula:Dividing in a Ratio

    $\text{share} = \dfrac{\text{part}}{\text{total parts}} \times T$

    View formula →
14. 14.

    A circle has a radius of 13 cm. Find its area. (Use π ≈ 3.14159)

    Formula:Area of a Circle

    $A = \pi r^2$

    View formula →
15. 15.

    Solve for x: 6x + 5 = 53.

    Formula:Solving a Linear Equation

    $x = \dfrac{c - b}{a}$

    View formula →
16. 16.

    A car travels 100 km in 2 hours. Find its average speed.

    Formula:Speed

    $v = \dfrac{d}{t}$

    View formula →
17. 17.

    What is 20% of 200?

    Formula:Percentage of a Quantity

    $\text{result} = \dfrac{p}{100} \times N$

    View formula →
18. 18.

    A train moves at 30 km/h for 5.3 hours. How far does it travel?

    Formula:Distance from Speed & Time

    $d = v \times t$

    View formula →
19. 19.

    A right-angled triangle has legs of 10 cm and 15 cm. Find the length of the hypotenuse.

    Formula:Pythagorean Theorem

    $c = \sqrt{a^2 + b^2}$

    View formula →
20. 20.

    Convert 9.5 kilometres into metres.

    Formula:Metric Length Conversion

    $1\,\text{km} = 1000\,\text{m}$

    View formula →

© FormulaWon — formulawon.app · Answers & step-by-step working available on the solutions sheet.