GCSE Mathematics Targeting Grade C Handling Data Unit 4 Pie Charts Can you: If not you need TOP: Revise angles Practice 1: How to draw a pie chart •Draw a pie chart •Answer questions from pie charts Try a test Practice 2: Answer questions about pie charts TAIL TOP 1) 2) 3) 4) 5) 6) 7) 8) Are you ready for the answers ? How many degrees in a circle? How many degrees in a triangle? How many degrees in a right angle? How do we recognize a right angle? What makes a triangle isosceles? How do we know if a triangle is equilateral? How many degrees in a quadrilateral? What do we know about an interior and exterior angle? 9) What do all exterior angles add up to? 10) Write a fact about scalene triangles. Lesson Answers 1) 360º 2) 180º 3) 90º 4) Looks like a square 5) Two equal sides, two equal angles 6) All sides and angles equal 7) 360º 8) Add up to 180º 9) 360º 10) All sides and angles are different Practice 1: 1) 2) Draw the pie charts from the tables below. Activity Frequency Gym 4 Swimming 12 Squash 3 Aerobics 11 Total 30 Remember: Step 1: Total frequency if not given Step 2: 360º Total Frequency Step 3: Multiply each group by the answer to Step 2 Type of Pet Frequency Cat 30 Step 4: Draw the pie chart Dog 25 Step 5: Label carefully Rabbit 15 Other 20 Total 90 Lesson Practice 2: 1) The pie chart shows how Jenny spends her monthly income. Jenny spends £150 a month on food. (a) Work out Jenny’s monthly income (b) Work out how much Jenny spends on rent each month. Clothes & Going Out Food Savings Other Bills 120º Rent Next Put the angle in the pie chart over 360 (like a fraction), cancel down if possible and then relate it to the money Jenny has. 2) The pie chart gives information about the bills paid by a Water Company. (a) Work out the size of the angle representing Wages. The Water Company spent £18 000 on Materials. (b) Work out the amount it spent on Rates. Lesson TAIL 1) Patrick carried out a survey of 45 pupils in Year 11. He asked how many books they had borrowed from the library in the last month. These are Patrick’s results. (a) Copy and complete the table. Number of books 0 to 2 3 to 5 6 to 8 more than 8 Tally Frequency 6 (b) Construct a pie chart to show this information. Are you ready for the answers ? Next Answers to Q1 Number of books 0 to 2 3 to 5 6 to 8 more than 8 Tally Frequency 11 15 13 6 Angles : 11 8 = 88º 15 8 = 120º 13 8 = 104º 6 8 = 48º Next 2) In a town, 1800 cars were stolen in a year. The table show information about the times of day in which they were stolen. Time Number of cars Midnight to 6 am 6 am to midday Midday to 6 pm 6 pm to midnight Time unknown 700 80 280 470 270 This information can be shown on a pie chart. (a) Copy out the table below and work out the angles for each sector. Time Midnight to 6 am 6 am to midday Midday to 6 pm 6 pm to midnight Time unknown Total of angles Angle of sector Are you ready for the answers ? 360º (b) Construct the pie chart. (c) What fraction of cars were stolen between midday and 6pm. Write your answer in its simplest terms. Next Answers to Q2. Angles: 700 0.2 = 140º 80 0.2 = 16º 280 0.2 = 56º 470 0.2 = 94º 270 0.2 = 140º (c) 280 = 7 1800 Lesson 45