1. Targeting Grade C Handling Data Unit 2 Averages GCSE Mathematics

2. Can you … Find mean, median and mode from a table of data Find the median and mode from a grouped table Find the mean from a grouped table Try a test TOP: Practise finding averages from a list of data Practice 1: Find averages from a table Practice 2: Find median and mode from a grouped table Practice 3: Find mean from a grouped table TAIL If not you need

3. TOP:For the following lists of data, find the mean, mode and median. Remember: Mode = Most common or most frequent number Median = Middle number AFTER they have been put in order Mean = add all the numbers together and then divided by how many numbers in the list. 1)412, 426, 435, 412, 427, 428, 435 2)27, 29, 27, 25, 24, 27, 25, 29 3)4, 6, 4, 8, 9, 2, 4, 6, 7, 8, 6, 5, 5, 4, 6 4)101, 106, 99, 108, 76, 87, 102, 93 Lesson 1)Mean = 425, Mode = 412 & 435, Median = 427 2)Mean = 26.625, Mode = 27, Median = 27 3)Mean = 5.6, Mode = 4 & 6, Median = 6 4)Mean = 96.5, Mode = none, Median = 100 Are you ready for the answers ?

4. Practice 1: Find the mean, median and mode from the following tables. 1)A shop sells tins of beans at half price. Ten people leaving the shop are asked how many tins they bought. The table shows their results. 2)Some students took a mental arithmetic test. Their marks are given in the table below. Next Why not use the Greek letter  (or sigma) instead of the word ‘total’.

5. 3)Rosie has 10 boxes of drawing pins. She counted the number of drawing pins in each box. The results are in the table below. Lesson

6. Practice 2: For the following grouped tables, find the median and modal classes (modal means mode!) 1) 2) Lesson Mark in TestFrequency 1 – 203 21 – 4010 41 – 6017 61 – 806 81 – 1004 Total (Σ)30 Remember: Finding the cumulative frequency may help you find the median and mode Temperature °CFrequency 0 – 522 6 – 1061 11 – 1584 16 – 2074 21 – 2556 26 – 3015 Total (Σ)312

7. Practice 3: For the following grouped tables, find the mean. 1) Next DARTS RESULTS ScoreFrequencyMid-point X f  X 1 – 203 21 – 4017 41 – 6025 61 – 8056 81 – 1008 101 – 1203 TOTAL Find the mid-point of the score column first, then multiply it by the frequency column.

8. 2) Mass (kg)FrequencyMid-point Xf × X 60 – 644 65 – 6927 70 – 7442 75 – 7960 80 – 8435 85 – 8912 Σ Lesson

9. TAIL 1) For the given tables, work out the mean, median and mode. Number of petsFrequency 1 – 25 3 – 48 5 – 612 7 – 814 9 – 1013 11 – 126 13 – 142 Σ Are you ready for the answers ?

10. Number of petsFrequencyMid – pointf × x 1 – 251.57.5 3 – 483.528 5 – 6125.566 7 – 8147.5105 9 – 10139.5123.5 11 – 12611.569 13 – 14213.527 Σ 60426 Answers for Q1 Mean = 426 ÷ 60 = 7.1 Median class = 7 – 8 Modal class = 7 – 8 Next

11. 2) Number of matches per box Frequency 474 4820 4935 5024 5117 Σ 100 Are you ready for the answers ?

12. Answers for Q2 Number of matches per box Frequencyf × x 474188 4820960 49351715 50241200 5117867 Σ 1004930 Mean = 4930 ÷ 100 = 49.3 Median = 49 Mode = 49 Lesson