Member of the e-learning unit in Newcastle University's School of Mathematics and Statistics.

Lead developer of Numbas.

I'm happy to answer any questions - email me.

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Christian Lawson-Perfect on Rearranging Logarithms involving Indices 8 years, 5 months ago

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Christian Lawson-Perfect on Rearranging Logarithms involving Indices 8 years, 5 months ago

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Christian Lawson-Perfect on Discrete and continuous data 8 years, 5 months ago

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Christian Lawson-Perfect on Discrete and continuous data 8 years, 5 months ago

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Lovely examples, but the explanations are wrong. 

A simple definition of continuous is that in between two measurements there's always a valid "middle" measurement. So between 56.3cm and 56.4cm there's 56.35cm. But the number of cinema tickets sold is discrete because there's nothing between 1 and 2 tickets sold.

Can you rewrite the explanations using this definition?

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Christian Lawson-Perfect on Converting between Mixed Numbers and Improper Fractions 8 years, 5 months ago

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Christian Lawson-Perfect on Converting between Mixed Numbers and Improper Fractions 8 years, 5 months ago

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In the advice, I don't find the justifications for parts a and b very clear at all. I'd say, for example, "$\frac{3}{18}  = \frac{3}{3} \times \frac{1}{6}$", not "$1 \times 3 = 3$ and $6 \times 3 = 18$ to give $\frac{3}{18}$". The latter looks like it's working backwards. Your worked solution should reproduce the steps a student could take to get to the right answer.

The formatting in the advice for part c has gone awry, with some lines centred that shouldn't be.

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Christian Lawson-Perfect on Using Laws for Addition and Subtraction of Logarithms 8 years, 5 months ago

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Christian Lawson-Perfect on Using Laws for Addition and Subtraction of Logarithms 8 years, 5 months ago

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The gaps should be number entry parts, not mathematical expressions.

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Christian Lawson-Perfect on Percentages and ratios - box of chocolates 8 years, 5 months ago

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Christian Lawson-Perfect on Percentages and ratios - box of chocolates 8 years, 5 months ago

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Good question!