Brazil · Ano 7 · Practice Sheet 31

1. 1.

   R$ 4,400 is invested at 3% simple interest per year for 5 years. Find the interest earned.

   Formula:Simple Interest

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

   View formula →
2. 2.

   Find the area of a square with side length 28 cm.

   Formula:Area of a Square

   $A = s^2$

   View formula →
3. 3.

   Find the circumference of a circle whose radius is 22 m. (Use π ≈ 3.14159)

   Formula:Circumference of a Circle

   $C = 2\pi r$

   View formula →
4. 4.

   A triangle has a base of 23 cm and a height of 28 cm. Find its area.

   Formula:Area of a Triangle

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

   View formula →
5. 5.

   A rectangle is 19 cm long and 7 cm wide. Find its area.

   Formula:Area of a Rectangle

   $A = l \times w$

   View formula →
6. 6.

   A right-angled triangle has legs of 8 cm and 7 cm. Find the length of the hypotenuse.

   Formula:Pythagorean Theorem

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

   View formula →
7. 7.

   A value changes from 69 to 152. Find the percentage change (to 2 d.p.).

   Formula:Percentage Change

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

   View formula →
8. 8.

   A bag has 30 equally likely marbles, of which 9 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 →
9. 9.

   A triangle has a base of 34 cm and a height of 11 cm. Find its area.

   Formula:Area of a Triangle

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

   View formula →
10. 10.

    A right-angled triangle has legs of 16 cm and 14 cm. Find the length of the hypotenuse.

    Formula:Pythagorean Theorem

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

    View formula →
11. 11.

    A circle has a radius of 25 cm. Find its area. (Use π ≈ 3.14159)

    Formula:Area of a Circle

    $A = \pi r^2$

    View formula →
12. 12.

    Convert 2.89 kilometres into metres.

    Formula:Metric Length Conversion

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

    View formula →
13. 13.

    One item costs R$ 23.6. Find the total cost of 16 items.

    Formula:Total Cost

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

    View formula →
14. 14.

    A train moves at 50 km/h for 1.9 hours. How far does it travel?

    Formula:Distance from Speed & Time

    $d = v \times t$

    View formula →
15. 15.

    A circle has a radius of 14 cm. Find its area. (Use π ≈ 3.14159)

    Formula:Area of a Circle

    $A = \pi r^2$

    View formula →
16. 16.

    A car travels 152 km in 4 hours. Find its average speed.

    Formula:Speed

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

    View formula →
17. 17.

    Solve for x: 3x + 1 = 34.

    Formula:Solving a Linear Equation

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

    View formula →
18. 18.

    What is 20% of 60?

    Formula:Percentage of a Quantity

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

    View formula →
19. 19.

    Find the mean (average) of these numbers: 21, 51, 34, 76.

    Formula:Arithmetic Mean

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

    View formula →
20. 20.

    R$ 3,900 is invested at 8% simple interest per year for 2 years. Find the interest earned.

    Formula:Simple Interest

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

    View formula →

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