Brazil · Ano 7 · Practice Sheet 44

1. 1.

   A circle has a radius of 18 cm. Find its area. (Use π ≈ 3.14159)

   Formula:Area of a Circle

   $A = \pi r^2$

   View formula →
2. 2.

   Find the mean (average) of these numbers: 27, 20, 27, 78, 38.

   Formula:Arithmetic Mean

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

   View formula →
3. 3.

   A triangle has a base of 9 cm and a height of 21 cm. Find its area.

   Formula:Area of a Triangle

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

   View formula →
4. 4.

   Find 7/8 of 80.

   Formula:Fraction of a Quantity

   $\text{result} = \dfrac{a}{b} \times N$

   View formula →
5. 5.

   One item costs R$ 19.94. Find the total cost of 19 items.

   Formula:Total Cost

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

   View formula →
6. 6.

   A value changes from 125 to 84. Find the percentage change (to 2 d.p.).

   Formula:Percentage Change

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

   View formula →
7. 7.

   R$ 120 is shared in the ratio 5 : 5. Find each share.

   Formula:Dividing in a Ratio

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

   View formula →
8. 8.

   A bag has 22 equally likely marbles, of which 21 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.

   Find 1/4 of 60.

   Formula:Fraction of a Quantity

   $\text{result} = \dfrac{a}{b} \times N$

   View formula →
10. 10.

    Find the mean (average) of these numbers: 34, 59, 98, 35, 67, 55.

    Formula:Arithmetic Mean

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

    View formula →
11. 11.

    What is 12% of 110?

    Formula:Percentage of a Quantity

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

    View formula →
12. 12.

    A car travels 282 km in 3 hours. Find its average speed.

    Formula:Speed

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

    View formula →
13. 13.

    A value changes from 134 to 85. Find the percentage change (to 2 d.p.).

    Formula:Percentage Change

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

    View formula →
14. 14.

    R$ 900 is invested at 7.5% simple interest per year for 2 years. Find the interest earned.

    Formula:Simple Interest

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

    View formula →
15. 15.

    A value changes from 132 to 108. Find the percentage change (to 2 d.p.).

    Formula:Percentage Change

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

    View formula →
16. 16.

    A rectangle is 13 cm long and 28 cm wide. Find its area.

    Formula:Area of a Rectangle

    $A = l \times w$

    View formula →
17. 17.

    Find the circumference of a circle whose radius is 6 m. (Use π ≈ 3.14159)

    Formula:Circumference of a Circle

    $C = 2\pi r$

    View formula →
18. 18.

    Find 7/8 of 88.

    Formula:Fraction of a Quantity

    $\text{result} = \dfrac{a}{b} \times N$

    View formula →
19. 19.

    Convert 10.1 kilometres into metres.

    Formula:Metric Length Conversion

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

    View formula →
20. 20.

    A value changes from 76 to 170. Find the percentage change (to 2 d.p.).

    Formula:Percentage Change

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

    View formula →

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