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      Checking and securing understanding of converting between ratios, percentages and fractions

      Lesson details

      Learning outcome

      I can move fluently between a ratio, percentage and fractions and compare these.

      Key learning points

      1. A multiplicative relationship can be described by a ratio.
      2. A multiplicative relationship can be described by a percentage.
      3. A multiplicative relationship can be described by a fraction.
      4. It is therefore possible to move between ratio, percentages and fractions.

      Keywords

      • Ratio - A ratio shows the relative sizes of 2 or more values and allows you to compare a part with another part in a whole

      Common misconception

      Converting a ratio e.g. 1 : 3 to 1/3 as a fraction.

      Drawing out simple ratios using bars can help pupils to see how fractions can correctly be obtained from a given ratio.

      Teacher tip

      Pupils will benefit from many opportunities to use fractions, ratios and percentages interchangeably but may also need support in breaking down 'longer' problems where lots of information is given in these different forms.

      Licence

      This content is © Oak National Academy Limited (2026), licensed on Open Government Licence version 3.0
      except where otherwise stated. See Oak's terms & conditions
      (Collection 2).

      Lesson video

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      Prior knowledge starter quiz

      6 Questions

      Q1.
      Select the ratios that are equivalent to 5 : 7.

      7 : 5
      6 : 8
      Correct answer: 12.5 : 17.5
      Correct answer: 15 : 21

      Q2.
      Alex and Sofia share some money in the ratio 5 : 7. They share £420 in total. How much does Sofia get?

      Correct answer: £245
      £175
      £60
      £588

      Q3.
      Alex and Sofia share some money in the ratio 5 : 7. Alex gets £420. How much does Sofia get?

      Correct answer: £588
      £245
      £175
      £300

      Q4.
      Alex and Sofia share some money in the ratio 5 : 7. Sofia gets £420. How much did they share in total?

      Correct answer: £720
      £588
      £245
      £175

      Q5.
      Alex and Sofia share some money in the ratio 5 : 7. Sofia gets £420 more than Alex. How much did Alex get?

      Correct answer: £1050
      £1470
      £720
      £175

      Q6.
      Izzy, Laura and Jun share some money in the ratio of 7 : 3 : 2. Jun gets £60 less than Laura. How much does Izzy receive?

      Correct answer: £420
      £105
      £35
      £300

      6 Questions

      Q1.
      There are only red and green sweets in a bag. If the ratio of red to green is 2 : 5 what fraction of the sweets in the bag are red?

      $$\frac{2}{5}$$
      Correct answer: $$\frac{2}{7}$$
      $$\frac{5}{7}$$
      $$\frac{3}{4}$$

      Q2.
      There are only cars or bikes in a car park. If 20% are bikes, what is the ratio of cars : bikes?

      1 : 4
      20 : 100
      1 : 5
      Correct answer: 4 : 1
      5 : 1

      Q3.
      There are only red, yellow and green marbles in a bag. If $$\frac{1}{2}$$ are red, $$\frac{1}{6}$$ are yellow, write the ratio of red to yellow to green marbles.

      Correct Answer: 3 : 1 : 2, 3:1:2

      Q4.
      A bag of sweets contains red, yellow and green sweets. There are 180 sweets in the bag. 25% of them are red. The rest are yellow and green in the ratio 7 : 2 How many yellow sweets are there?

      Correct Answer: 105

      Q5.
      Laura and Sofia share some money in the ratio 3 : 5 Laura gives $$\frac{2}{5}$$ of her money to Jacob. If Jacob gets £24, how much does Sofia get?

      Correct Answer: 100

      Q6.
      Jacob, Andeep and Lucas receive some money. Jacob gets $$\frac{3}{5}$$ of the money. Andeep and Lucas share the rest in the ratio 5 : 2 What proportion of the prize money does Andeep get?

      $$\frac{2}{5}$$
      $$\frac{5}{7}$$
      Correct answer: $$\frac{10}{35}$$
      $$\frac{15}{35}$$

      To help you plan your 10 maths lesson on: Checking and securing understanding of converting between ratios, percentages and fractions, download all teaching resources for free and adapt to suit your pupils' needs...