Thailand · Grade 7 · Practice Sheet 3

1. 1.

   A value changes from 156 to 232. Find the percentage change (to 2 d.p.).

   Formula:Percentage Change

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

   View formula →
2. 2.

   What is 15% of 330?

   Formula:Percentage of a Quantity

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

   View formula →
3. 3.

   Find the mean (average) of these numbers: 33, 81, 80, 62.

   Formula:Arithmetic Mean

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

   View formula →
4. 4.

   Solve for x: 6x + 15 = 57.

   Formula:Solving a Linear Equation

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

   View formula →
5. 5.

   Find 7/8 of 144.

   Formula:Fraction of a Quantity

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

   View formula →
6. 6.

   A value changes from 47 to 24. 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.

   What is 20% of 550?

   Formula:Percentage of a Quantity

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

   View formula →
8. 8.

   Convert 5.57 kilometres into metres.

   Formula:Metric Length Conversion

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

   View formula →
9. 9.

   A bag has 20 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 →
10. 10.

    Find the mean (average) of these numbers: 30, 45, 64, 57, 70, 20.

    Formula:Arithmetic Mean

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

    View formula →
11. 11.

    Find the perimeter of a rectangle measuring 44 m by 34 m.

    Formula:Perimeter of a Rectangle

    $P = 2(l + w)$

    View formula →
12. 12.

    One item costs ฿18.91. Find the total cost of 10 items.

    Formula:Total Cost

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

    View formula →
13. 13.

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

    Formula:Simple Interest

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

    View formula →
14. 14.

    What is 5% of 360?

    Formula:Percentage of a Quantity

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

    View formula →
15. 15.

    A triangle has a base of 14 cm and a height of 25 cm. Find its area.

    Formula:Area of a Triangle

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

    View formula →
16. 16.

    Find the mean (average) of these numbers: 81, 67, 58, 75, 15, 48.

    Formula:Arithmetic Mean

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

    View formula →
17. 17.

    ฿231 is shared in the ratio 5 : 2. Find each share.

    Formula:Dividing in a Ratio

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

    View formula →
18. 18.

    Find 1/3 of 45.

    Formula:Fraction of a Quantity

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

    View formula →
19. 19.

    A right-angled triangle has legs of 3 cm and 5 cm. Find the length of the hypotenuse.

    Formula:Pythagorean Theorem

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

    View formula →
20. 20.

    Find 1/5 of 55.

    Formula:Fraction of a Quantity

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

    View formula →

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