Transition to university

Vicky Hall commented on Factorising Quadratic Equations with $x^2$ Coefficients Greater than 1 8 years, 5 months ago

The statement is exactly the same as the other quadratic equations questions, but this time its not true that $ax^2+bx+c$ factorises to $(x+m)(x+n)$ - the $x$s need coefficients.

I think there should be two more parts to this question, a question at the beginning that only wants to students to factorise, and a question at the end that doesn't give them one of the $x$ coefficients.

It would also be very helpful to tell students in the statement that we can sometimes divide through by the $x^2$ coefficient to obtain a simpler equation, but sometimes the coefficent is not a factor of all terms so we can't. (I know you show this in the advice but it would be nice for the student to see this before they try the question as otherwise they will start looking for factors of the existing numbers). 

Vicky Hall on Cumulative percent decrease 8 years, 5 months ago

Gave some feedback: Has some problems

Vicky Hall commented on Cumulative percent decrease 8 years, 5 months ago

Make sure all number are in Latex. I think the statement needs changing 

Check your tenses. For example, 'How much is it worth after 5 months?' would read much better as 'How much will it be worth after 5 months?'. Also, 'After how many more months is the smartphone's value going to be £511.19?' would be better as 'After how many more months will the smartphone's value be £511.19?'.

In part c), I would say leave out the word 'exponentially' and change the next sentence to say 'What was the average percentage increase per year?'.

Elliott Fletcher commented on Creating Frequency Tables 8 years, 5 months ago

Thanks for the feedback Vicky, i asked Christian and he helped me make the numbers variable

Elliott Fletcher on Creating Frequency Tables 8 years, 5 months ago

Gave some feedback: Needs to be tested

Bradley Bush commented on Expand brackets and collect like terms 8 years, 5 months ago

Thank you for the feedback and s0rry for the typing errors. Changing the marking order was very difficult but has been done using either string restrictions or marking scripts. Thank you for the advice for the wording of wuestions, I need to get more concise with the way I word things. I am glad you liked it.

Hannah Aldous commented on Calculate the original price before a decrease 8 years, 5 months ago

I corrected some grammar in the statement and question, but otherwise I think it sounds good. 
I'm not sure you need the first part of your advice becase I don't think students would find it helpful compared to your actual advice.
I don't think Divide needs a capital d as it is the middle of a sentence.
otherwise I think your question looks good

Vicky Hall commented on Factorising Quadratic Equations with $x^2$ Coefficients of 1 8 years, 5 months ago

I think this question should be renamed to 'factorising quadratic equations with $x^2$ coefficient $1$, and your other question (Factoring quadratics with larger coefficients) should be renamed 'factorising quadratic equations with $x^2$ coefficient greater than $1$.

There should be another line in the statement that shows how to solve the equation if it factorises to $(x+m)(x+n)=0$, as you ask the student to solve in the final part of the question. 

In part a), I think it's a good idea to have a difference of two squares example to get students to think about how the equation can sometimes look a bit different. However, I think this should be moved to a subpart iii), and subpart i) should have a straightforward quadratic that looks exactly like the general form $ax^2+bx+c$.

Vicky Hall on Factorising Quadratic Equations with $x^2$ Coefficients of 1 8 years, 5 months ago

Gave some feedback: Has some problems

Hannah Aldous on Calculate the original price before a decrease 8 years, 5 months ago

Gave some feedback: Has some problems

Hannah Aldous on Calculate the original price before a decrease 8 years, 5 months ago

Gave some feedback: Doesn't work

Vicky Hall on Using a speed and acceleration graph 8 years, 5 months ago

Gave some feedback: Has some problems

Vicky Hall commented on Using a speed and acceleration graph 8 years, 5 months ago

You need to shift the $x$ axis up so it joins the $y$ axis at $(0,0)$. The graph looks very unusual with the $x$ axis where it is and it also makes it hard to see that some of the accelerations are negative. I also think that it would look better to have speed on one graph and acceleration on another. You could still ask the student to idenitfy which graph is which.

Make sure $\mathrm{metres}$ is spelt the English way.

I think $3$ questions on finding the distance is excessive - one where the area under the graph is a rectangle and another where it is not would suffice.

Currently the final part of the question just requires the student to add lots of numbers together. A better question would be to give them the distance travelled over the time periods they haven't yet calculated and ask them to calculate the average speed over the full time period. 

I actually think this could become two questions, one that looks at using a speed-time graph to find distance and one that looks at the relationship between speed and acceleration, as it is a long question assessing many aspects of the topic. It could also be good to encourage the student to think about what the speed-time graph will look like if the acceleration is not constant.

Hannah Aldous on Finding the formula for the $n^{\text{th}}$ term of linear sequences 8 years, 5 months ago

Gave some feedback: Needs to be tested

Hannah Aldous on Identifying different types of sequences 8 years, 5 months ago

Gave some feedback: Needs to be tested

Lauren Richards on Finding the highest common factor of two numbers 8 years, 5 months ago

Gave some feedback: Has some problems

Elliott Fletcher commented on Extract common factors of polynomials 8 years, 5 months ago

Main Parts

a) i) good

ii) There is an issue with the marking here, i had 102y+12y^2, and had the answer as 6*y*(17+2*y) which was marked incorrect and the displayed answer was 6*y(2y+17).

iii) Again there is an issue with the marking here.

In the question you don't write an * between each of the algebraic variables in the first term, making it look different to the other term. I think this then creates an issue in the marking as the displayed answer i got was xyz(41xyz+3) so the answer is only correct if you don't include the * between the variables even though in the statement you tell the students to include the * in their answer.

iv) good

v) again there is an issue with the marking here in the same way as in iii)

b)

iii) there is an issue with the marking here too, even inputting the displayed answer is marked incorrect as numbas thinks it is not a valid mathematical expression.

Advice

a) (all questions) i would write any products in brackets just for neatness, e.g 74x+62 = (2*37x)+(2*31).

Also, be careful when writing out big products of variables like xyz, i think you need to have an * between each variable

And i think there should be full stops at the end of each calculation.

b)

I think the formula for the quadratic equation should be ax^2+bx+c = (x+n1)(x+n2)

iii) i would put brackets around the products here.

Sorry for all the feedback!

Elliott Fletcher on Extract common factors of polynomials 8 years, 5 months ago

Gave some feedback: Has some problems

Elliott Fletcher commented on Square and cube numbers 8 years, 5 months ago

Main Parts

a) i would write (x_n)^2 instead of x^2.

b) i would write (x_n)^3 instead of x^3. Also, its up to you but you could maybe include (x_5)^3 as an extra question here.

c) i think there should be a full stop after the inequality here.

Advice

a) i think there should be full stops at the end of each of the calculations, like after the 9 in the calculation for 3^2.

b) again i think there should be full stops at the end of each of the calculations.

c) i would say "Here is a table of square numbers for integers from 1-15"

I would also include an extra sentence before you calculate the square root of y^2. You could say "To calculate y we must calculate the square root of y^2," and then have a full stop at the end of the equation here as well.

Otherwise, this looks good!