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### History and Feedback

#### Checkpoint description

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#### Chris Graham2 years, 1 month ago

Gave some feedback: Ready to use

#### Chris Graham2 years, 1 month ago

I've split off the prime numbers part into its own question and re-used the variables from part a) in b) and c), so that the parts lead on from eachother.

Published this.

#### Lauren Richards2 years, 2 months ago

In part c)i), ii) and iii), I really wanted the individual factors to be listed for each number, and then for the common factors in each individual list to be highlighted but I didn't know how to do this and I think Chris mentioned something would have to be created in order to do this.

#### Lauren Richards2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Chris Graham2 years, 2 months ago

I had 25 marked as prime in part b). I think you may need to update the marking matrix after removing the choice below?

#### Chris Graham2 years, 2 months ago

Gave some feedback: Has some problems

#### Lauren Richards2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Chris Graham2 years, 2 months ago

Gave some feedback: Has some problems

#### Chris Graham2 years, 2 months ago

I think I would avoid 1 as an option altogether in part (b). Whether 1 is prime or not will trip up a lot of students but is unlikely to be of importance in their studies; I think it's more important to test their knowledge of whether a number is or isn't composite, rather than catch them out on (arguably) a technicality.

RE your problem in the comment below: h/6 is less than 6 ~50% of the time, so you could either re-think your variables, or use sort to arrange into the correct order, for example set up a new list of numbers containing the factors... sort([1,2,3,h/6,6...]).

There's a mix of singular and plural in the statement. I think I would write "A number that can be...".

"divided evenly by whole numbers" would be better as "divided without remainder..." to avoid confusion with even numbers.

Part (c) in the advice does not provide much additional informtation. I guess you haven't included all of the factors as it would be a pain! That's fine I think.

#### Lauren Richards2 years, 2 months ago

- There is a slight problem with variable h in the table in that sometimes its divisors are not in the right order.

#### Lauren Richards2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Elliott Fletcher2 years, 2 months ago

Gave some feedback: Has some problems

#### Elliott Fletcher2 years, 2 months ago

I think this is a really good question and it works well. Just a few comments

Main Parts

In the statement i would write a definition of composite as well as some students might not know what this means.

a) good

b) in the question i would write "Identify which of the following are prime numbers:" instead of "Identify the prime numbers from below."

One of the numbers here for me was 43, which is a prime number, however if you say it is a prime number it is marked incorrect as the displayed answer is that it is composite.

Good job getting the list of factors thing to work!

b) you could put the numbers in the table in the order that they appear in the question but it's up to you. I would also write "composite" instead of "not prime".

Also you could extend the table a little bit to the right, so that some numbers don't go onto a new line in the divisors column.

#### Lauren Richards2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Lauren Richards2 years, 2 months ago

Gave some feedback: Has some problems

#### Lauren Richards2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Vicky Hall2 years, 2 months ago

Also, the bit in the advice that says 'Whilst $1$ technically fits the criteria for a prime number, it is not considered a prime number' needs to be changed. $1$ does not meet the criteria for being a prime as it only divides by $1$, whereas all other primes have two distinct divisors, themselves and $1$.

#### Vicky Hall2 years, 2 months ago

Gave some feedback: Has some problems

#### Vicky Hall2 years, 2 months ago

I would change the title to 'Identifying prime numbers' to make it clearer what the question is about. In the question I would change the word 'composite' to 'not prime', just to make the language a bit simpler.

#### Lauren Richards2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Lauren Richards2 years, 2 months ago

Created this.
Finding the highest common factor of two numbers Ready to use Lauren Richards 01/08/2017 11:30
Prime numbers Ready to use Chris Graham 01/08/2017 11:31
ggd om breuken te vereenvoudigen draft Johan Maertens 30/11/2017 17:28
Marlon's copy of Prime numbers draft Marlon Arcila 03/02/2018 16:22

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