Using a calculator, work out the mean for each of these frequency tables, give your answers to two decimal places.
", "advice": "To calculate the mean shoe size we need to add a third column to our table where we multiply the grade by the number (frequency) of students who are that shoe size.
\n| Shoe Size | \nFrequency | \nShoe Size * Frequency | \n
| 3 | \n{p1} | \n3 * {p1} = {3*p1} | \n
| 4 | \n{p2} | \n4 * {p2} = {4*p2} | \n
| 5 | \n{p3} | \n5 * {p3} = {5*p3} | \n
| 6 | \n{p4} | \n6 * {p4} = {6*p4} | \n
| 7 | \n{p5} | \n7 * {p5} = {7*p5} | \n
| 8 | \n{p6} | \n8 * {p6} = {8*p6} | \n
Now we find the total sum of that third column:
\n$\\var{3*p1} + \\var{4*p2} + \\var{5*p3} + \\var{6*p4} + \\var{7*p5} + \\var{8*p6} = \\var{3*p1 + 4*p2 + 5*p3 + 6*p4 + 7*p5 + 8*p6}.$
\nTo find the mean shoe size we must divide this total by the total number of students:
\n$\\frac{\\var{3*p1 + 4*p2 + 5*p3 + 6*p4 + 7*p5 + 8*p6}}{\\var{p1}+\\var{p2}+\\var{p3}+\\var{p4}+\\var{p5}+\\var{p6}} = \\frac{\\var{3*p1 + 4*p2 + 5*p3 + 6*p4 + 7*p5 + 8*p6}}{\\var{sum1}} = \\var{mean1a}.$
\nThe question asks us for our answer to two decimal places so the last thing we need to do is round. Hence, the mean is $\\var{mean1}$.
\nYou can use this same method to answer the other parts of this question!
\nUse this link to find some resources which will help you revise this topic.
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\n| Shoe size | \nFrequency | \n
| 3 | \n{p1} | \n
| 4 | \n{p2} | \n
| 5 | \n{p3} | \n
| 6 | \n{p4} | \n
| 7 | \n{p5} | \n
| 8 | \n{p6} | \n
The table below shows the distribution of number of pets that {sum2} randomly asked people have.
\n| Number of Pets | \nFrequency | \n
| 0 | \n{p1b} | \n
| 1 | \n{p2b} | \n
| 2 | \n{p3b} | \n
| 3 | \n{p4b} | \n
The table below shows the distribution of the number of drinks per order at a coffee shop in Manchester.
\n| Number of Drinks | \nFrequency | \n
| 0 | \n{p1c} | \n
| 1 | \n{p2c} | \n
| 2 | \n{p3c} | \n
| 3 | \n{p4c} | \n
| 4 | \n{p5c} | \n
| 5 | \n{p6c} | \n