Grouped Frequency Tables Averages Worksheet A Printing To

Grouped Frequency Tables – Averages – Worksheet A

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Averages from Grouped Frequency Tables Anne’s tallest friend is 140 cm tall. Her shortest friend is 120 cm tall. Anne and her four other friends are between these heights. What is a good estimate of the mean height of Anne’s group of friends? When we use data that is in groups, we must use the midpoint of each group to estimate averages. The frequency table below shows the height of everyone in Anne’s class. 1) Which groups are these students in? Alice is 132 cm tall. Arjun is 130 cm tall. Height, h (cm) Frequency Group Midpoint 4 115 Andy is 140 cm tall. Estimated Group Value (Frequency × Midpoint) 2 4 5 2 Totals Class Total = We can use this data to find an estimated mean. 2) Find the midpoint of each group and complete that column. 3) Find the total value of each group (multiply the frequency by the midpoint). 4) Find the class total by adding all the estimated group values. Estimated Mean = Total data Total Frequency 5) Use this formula to find the estimated mean. Estimated Mean = 6) How many people are in Anne’s class? 7) How could we describe where the median is?

Averages from Grouped Frequency Tables Anne’s tallest friend is 140 cm tall. Her shortest friend is 120 cm tall. Anne and her four other friends are between these heights. What is a good estimate of the mean height of Anne’s group of friends? When we use data that is in groups, we must use the midpoint of each group to estimate averages. The frequency table below shows the height of everyone in Anne’s class. 1) Which groups are these students in? Alice is 132 cm tall. Arjun is 130 cm tall. Height, h (cm) Totals Andy is 140 cm tall. Frequency Group Midpoint Estimated Group Value (Frequency × Midpoint) 4 115 460 2 125 250 4 135 540 5 145 725 2 155 310 17 Class Total = 2285 cm We can use this data to find an estimated mean. Answers 2) Find the midpoint of each group and complete that column. 3) Find the total value of each group (multiply the frequency by the midpoint). 4) Find the class total by adding all the estimated group values. Estimated Mean = Total data Total Frequency 5) Use this formula to find the estimated mean. 17 Estimated Mean = 6) How many people are in Anne’s class? 7) How could we describe where the median is? 134 cm

This table shows data for a different class. 8) Complete the table and find the estimated mean and the group with the median. Averages from Grouped Frequency Tables Anne’s tallest friend is 140 cm tall. Her shortest friend is 120 cm tall. Anne and her four other friends are between these heights. What is a good estimate of the mean height of Anne’s group of friends? Height, h (cm) When we use data that is in groups, we must use the midpoint of each group to estimate averages. The frequency table below shows the height of everyone in Anne’s class. 1) Which groups are these students in? Alice is 132 cm tall. Arjun is 130 cm tall. Height, h (cm) Totals Andy is 140 cm tall. Frequency Group Midpoint Estimated Group Value (Frequency × Midpoint) 4 115 460 2 125 4 Group Midpoint Estimated Group Value (Frequency × Midpoint) 2 125 250 6 135 810 4 145 580 3 155 465 15 Class Total = 2105 cm Estimated Mean = 140 cm Mr Higgins collected the data from his Geography test. 9) Complete the table and find the estimated mean and the median group. Frequency M F×M 250 7 10 70 135 540 11 30 330 5 145 725 13 50 650 2 155 310 17 Score, s (cm) Totals Answers 2) Find the midpoint of each group and complete that column. 3) Find the total value of each group (multiply the frequency by the midpoint). 4) Find the class total by adding all the estimated group values. Estimated Mean = Total data Total Frequency 5) Use this formula to find the estimated mean. Estimated Mean = 6) How many people are in Anne’s class? 7) How could we describe where the median is? 31 Class Total = 1050 marks Estimated Mean = 34 marks Class Total = 2285 cm We can use this data to find an estimated mean. 17 Frequency 134 cm 18. 5 people! 11) Complete this grouped frequency table and find an estimate for≈ 19 10) The pass mark was 30. How many people do you think passed the test? the mean and median. Score, s (cm) Frequency M F×M 5 15 75 7 45 315 9 75 675 4 105 420 Totals Mean = 59 25 marks Estimated Class Total = 1485 marks

Averages from Grouped Frequency Tables Anne’s tallest friend is 140 cm tall. Her shortest friend is 120 cm tall. Anne and her four other friends are between these heights. What is a good estimate of the mean height of Anne’s group of friends? This table shows data for a different class. 8) Complete the table and find the estimated mean and the group with the median. Height, h (cm) Frequency 6 4 3 The frequency table below shows the height of everyone in Anne’s class. Height, h (cm) Frequency Group Midpoint 4 115 Totals Andy is 140 cm tall. Estimated Group Value (Frequency × Midpoint) Estimated Mean = Group including Median = Mr Higgins collected the data from his Geography test. 9) Complete the table and find the estimated mean and the median group. Score, s (cm) Frequency 2 7 4 11 5 13 Totals 2 Estimated Mean = Totals Class Total = We can use this data to find an estimated mean. 2) Find the midpoint of each group and complete that column. 3) Find the total value of each group (multiply the frequency by the midpoint). 4) Find the class total by adding all the estimated group values. Estimated Mean = Total data Total Frequency 5) Use this formula to find the estimated mean. Group including Median = 10) The pass mark was 30. How many people do you think passed the test? 11) Complete this grouped frequency table and find an estimate for the mean and median. Score, s (cm) Frequency 5 675 Estimated Mean = 6) How many people are in Anne’s class? 7) How could we describe where the median is? Estimated Group Value (Frequency × Midpoint) 2 When we use data that is in groups, we must use the midpoint of each group to estimate averages. 1) Which groups are these students in? Alice is 132 cm tall. Arjun is 130 cm tall. Group Midpoint 420 Totals Mean = 25 Estimated Group including Median =

Questions? Comments? Suggestions? …or have you found a mistake!? Any feedback would be appreciated . Please feel free to email: tom@goteachmaths. co. uk