Transition to university

Bradley Bush on Find the equation of a line through two points - positive gradient 8 years, 5 months ago

Gave some feedback: Needs to be tested

Bradley Bush commented on Find the equation of a line through two points - positive gradient 8 years, 5 months ago

Thank you for the feedback Chris, I have done everything you've suggest4ed here as well as making the same changes to differenet versions of this question.

Christian Lawson-Perfect on Calculate the original price before a decrease 8 years, 5 months ago

Gave some feedback: Has some problems

Christian Lawson-Perfect on Calculate the original price before a decrease 8 years, 5 months ago

Saved a checkpoint:

Currently, the maximum price that can be picked is £800, and the maximum percentage change is 30%, giving a maximum original price of £1143. That's an enormous amount of money for a smartphone or a console! Maybe use a different range of prices for each item.

The "original" prices don't seem very realistic - they would typically be £xxx.99, just like the discounted price. Can you round off the original price, and make sure that the percentage discount is still the same?

Christian Lawson-Perfect on Square and cube numbers 8 years, 5 months ago

Gave some feedback: Has some problems

Christian Lawson-Perfect on Square and cube numbers 8 years, 5 months ago

Saved a checkpoint:

I don't think you need the $x_i$ notation. This question should test that the student knows what a superscript 2 or 3 means. This question could just be, "Find $5^2$"; "Find $3^3$"; "Find the first square number between $124$ and $165$".

Christian Lawson-Perfect on Rounding and estimating calculations 2 8 years, 5 months ago

Gave some feedback: Has some problems

Christian Lawson-Perfect on Rounding and estimating calculations 2 8 years, 5 months ago

Saved a checkpoint:

There are too many items in part a - I can't add them all up in my head. Just two or three items, plus the ice cream, would be enough to get the idea across.

Both parts a and b have this problem - even after rounding, I can't do these calculations in my head, so I might as well use a calculator. 

"The dimensions of the room are 6.49m×2.88m×3.39m where 3.39m is the height." is oddly worded. I'd say "The room measures 6.49m×2.88m, and 3.39m high."

In part b, I'd round to the nearest metre and do the calculation in my head. My maximum error when rounding to the nearest metre is $4 \times \left(\frac{1}{2}(\text{width}+\text{depth}+\text{height})+\frac{1}{4} \right)\text{m}^2$, which will be around one bucket's worth.

By the way, the height I got, 3.39m, is completely unrealistic! In the UK the minimum ceiling height is 2.1m and the standard is around 2.4m. 

The thesis of this question is that sometimes rounding to 1 sig fig is too blunt, but I don't think the given scenarios make a great case for it: they're all 'mental maths' scenarios. If I'm going to use a calculator, I might as well type in 2 decimal places rather than rounding to 1. Can you think of scenarios where you've got some very precise measurements, but only want a moderately precise answer? 

You could use the separate minimum and maximum accepted value settings for number entry parts in a question like this - accept anything within a generous bound of the true answer, and let the student perform whatever estimation they like, maybe guiding them towards one.

Stanislav Duris on Weight of a scoop in two ice cream parlours 8 years, 5 months ago

Gave some feedback: Needs to be tested

Elliott Fletcher on Which coin is more likely to be biased? 8 years, 5 months ago

Gave some feedback: Needs to be tested

Christian Lawson-Perfect on Factorising Quadratic Equations with $x^2$ Coefficients of 1 8 years, 5 months ago

Gave some feedback: Has some problems

Christian Lawson-Perfect on Factorising Quadratic Equations with $x^2$ Coefficients of 1 8 years, 5 months ago

Saved a checkpoint:

You need to write a feedback message to show when the student doesn't use brackets.

I got $x^2-16$ for part b, which I'd solve by noticing it's the difference of two squares. Can you make sure the coefficient $x$ is non-zero?

I'd spin part b into its own question: first factorise, then write down the roots.

Christian Lawson-Perfect on Simple interest 8 years, 5 months ago

Gave some feedback: Ready to use

Christian Lawson-Perfect on Simple interest 8 years, 5 months ago

Saved a checkpoint:

I've changed some of the wording, and used dpformat to make sure currency amounts are always shown to two decimal places. A good, simple question.

Elliott Fletcher on Probability - Notation and Conversion between Percentages, Decimals and Fractions 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: Needs to be tested

Hannah Aldous on Using the Quadratic Formula to Solve Equations of the Form $ax^2 +bx+c=0$ 8 years, 5 months ago

Gave some feedback: Needs to be tested

Christian Lawson-Perfect on Expand brackets and collect like terms 8 years, 5 months ago

Saved a checkpoint:

The string restrictions aren't doing a great job here. I don't think you should require the asterisk.

Talk to Elliott about adding pattern matching.

This should be two questions - a question with each of the items from part a as a separate part, and part b on its own.

Christian Lawson-Perfect on Expand brackets and collect like terms 8 years, 5 months ago

Gave some feedback: Has some problems

Chris Graham commented on Find the equation of a line through two points - positive gradient 8 years, 5 months ago

One more. If I do not attempt the question, but reveal the answers, then the advice refers to an absent green line. This is another good reason to put the correct plot in the advice.