Vicky Hall

Vicky Hall on Use formulae for the area and volume of geometric shapes 7 years, 5 months ago

Gave some feedback: Has some problems

Vicky Hall commented on Use formulae for the area and volume of geometric shapes 7 years, 5 months ago

The answer to part a) in the advice is wrong. There's also an issue with the answer to part b). You give all lengths and the angle to the student to two decimal places but then you calculate the answer using more decimal places, which makes your answer slightly more accurate than theirs can ever be. In the example I just did, it still rounds the same to two decimal places in the end (although it might not always) but it wasn't the same to five decimal places, which you give on the line above. This may seem like a small thing but it will confuse the student as no matter how many times they retype it they will not get the same answer as Numbas. You could fix this by rounding your numbers to two decimal places in the variables section.

The advice here is far too wordy. Try it shorten it to get straight to the point. In part a), for example, it would sound better to say:

'We can see from the diagram that the radius of the frisbee is $22\mathrm{cm}$. Replacing the letter $r$ in the formula for the area of a circle with $22$ gives....' etc.

Try to do this with all of the sections.

I have also put all occurences of $\mathrm{volume}$ and $\mathrm{area}$ into \mathrm and changed your American spelling of 'centimetres'.

Vicky Hall commented on Calculate the areas of polygons 7 years, 5 months ago

In parts a) and b), sometimes the answer is already an integer and doesn't need to be rounded so you end up with two identical lines in the advice. (Also, part a) doesn't round at all even when it should do so that needs to be fixed.) You can code your advice section so that certain lines only show if the solution does need to be rounded (I would speak to Lauren about it if you're not sure how as she has an example of this in one of her questions).

I have reworded part a) slightly to make it more succinct and I have also put the unit $\mathrm{m}$ into \mathrm. Have a look through the other parts and try to reword a bit more clearly. I agree with Hannah's advice:

\[\text{I think you need to start the advice for each part with 'The area of a parallelogram is calculated using the formula...'}\].

Vicky Hall on Basic Probability Questions 7 years, 5 months ago

Gave some feedback: Has some problems

Vicky Hall commented on Basic Probability Questions 7 years, 5 months ago

Good intro to basic concepts. Part c) seems a little contrived though - there's no way I would let my daughter pick a pet at random! Also, the outcomes are probably not equally likely because the child probably doesn't like each type of pet equally, and within each group there are likely to be distinctions too. I would think of another example where it makes sense to be randomly assigned something or to randomly pick something. The numbers need to be variables and you should let the student know to simplify their answer.

Vicky Hall commented on Always, sometimes or never: square and cube numbers 7 years, 5 months ago

I would remove the old bits. The same advice and more is now shown in the tables.

Vicky Hall commented on Use the factor theorem to identify factors of a polynomial 7 years, 5 months ago

I think this looks good Elliott!

Vicky Hall on Solving linear inequalities 7 years, 5 months ago

Gave some feedback: Has some problems

Vicky Hall commented on Solving linear inequalities 7 years, 5 months ago

In parts b), c) and d) the expected answer isn't simplified. I got $1$ for part b) but the answer displays as $\displaystyle\frac{3}{3}$. I agree that it's important to include questions that involve flipping the inequality sign as you have in parts d) and g), but my concern is that you have entered the correct inequality for the student and they may not notice that it has been switched around as their answer would be the same either way. I know you've highlighted this in the advice but if the student gets their answer marked right, they'll not read the advice. It could be good to change a couple of the questions (one where the inequality remains the same, the other where it has changed) so they have the choose the correct inequality from a drop down as well as enter a numerical value.

In part g) of the advice, the wrong variable has been entered in the first line of the solution.

Vicky Hall commented on Always, sometimes or never: square and cube numbers 7 years, 5 months ago

I really like the set up of this question and I think it will make the student think quite hard about properties of numbers. I've reworded some of the advice to make it clearer. I also think that, for consistency, parts vii) and viii) in the advice should have a table of values for $-3 \leq x\leq3$. It makes your conclusion look a bit stronger if you have checked a range of positive and negative numbers and can show a trend.