# Unit 3 Section 1 : Scatter graphs

Scatter graphs are a way of illustrating "paired" data - information about two related values.
For example : height and weight; price and sales; latitude and longtitude; rain and sunshine.

## Example Question

Look at the scatter graph below. The scatter graph shows height and age. Information for five girls has been plotted on the graph. Look at the point marked Emma. We can see from this point that Emma's height is 150 cm and her age is 8 years.
 Practice questions Work out the answer to each of these questions then click on the button marked to see whether you are correct. (a) Which girl is the tallest and how tall is she? (b) Which girl is the youngest and how old is she? (c) How much taller is Rebecca than Emma? (d) How much younger is Sarah than Samantha?

## Exercises

Work out the answers to the questions below and fill in the boxes. Click on the button to find out whether you have answered correctly. If you are right then will appear and you should move on to the next question. If appears then your answer is wrong. Click on to clear your original answer and have another go. If you can't work out the right answer then click on to see the answer.

Question 1
Ten children took part in a sponsored walk. The scatter plot shows how much money they raised and how far they walked.
 (a) How far did Karen walk? miles (b) How much money did Karen raise? £ (c) Who walked 20 miles and raised £40? Sally Sunniva Prakesh Karen John Nadida Rory Halim Bill Jane (d) How far did Bill walk? miles (e) How much money did Bill raise? £ (f) How much was Bill sponsored for each mile? £ per mile (g) How much was Sunniva sponsored for each mile? £ per mile

Question 2
The scatter plot below shows the ages of some children and the greatest distance they can swim.
 (a) Who is the youngest person who can swim 500m? Stewart Tony Alison Robin Frances Nesima Gita Zia Frederik (b) Who cannot swim at all? Stewart Tony Alison Robin Frances Nesima Gita Zia Frederik (c) Who is 8 and can swim 400m? Stewart Tony Alison Robin Frances Nesima Gita Zia Frederik (d) Who is 12 and can swim 350m? Stewart Tony Alison Robin Frances Nesima Gita Zia Frederik (e) Who is the youngest child? Stewart Tony Alison Robin Frances Nesima Gita Zia Frederik (f) Who swims furthest; Frances, Alison or Robin? Frances Alison Robin (g) Which ten-year-old is the weaker swimmer? Stewart Tony Alison Robin Frances Nesima Gita Zia Frederik

Question 3
In a sponsored swim, nine children each swam a certain distance and raised some money. In this question you will produce a scatter diagram for this information. You click on the graph to plot a point using the information in the table on the left. Then you check to see if you have plotted the point correctly by clicking on the button. If you plotted the point correctly, it will be ticked and will appear. If you see a cross on the point then you have made a mistake and must try again. You can remove points you have plotted incorrectly by clicking on them for a second time.

(a) Plot this information on the scatter diagram:

 Name Distance Money Check it! Mark 300 £12 Kingsley 500 £20 Caroline 200 £4 Kevin 400 £10 Pushpa 300 £8 Alex 250 £15 Jai 300 £20 Zahra 50 £10 Lynda 450 £18

(b) Complete this sentence by selecting a word:

"The children in the sponsored swim
who swam the furthest raised
money than the other children."

You have now completed Unit 3 Section 1
 Your overall score for this section is Correct Answers You answered questions correctly out of the questions in this section. Incorrect Answers There were questions where you used the Tell Me button. There were questions with wrong answers. There were questions you didn't attempt.
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