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#### Checkpoint description

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Published this.

#### Chris Graham3 years, 2 months ago

Gave some feedback: Ready to use

#### Chris Graham3 years, 2 months ago

I've made some very minor changes to the advice. Looks good now.

#### Lauren Richards3 years, 2 months ago

Gave some feedback: Needs to be tested

#### Christian Lawson-Perfect3 years, 2 months ago

Gave some feedback: Has some problems

#### Christian Lawson-Perfect3 years, 2 months ago

Saved a checkpoint:

I've removed the "without a calculator" bit - I don't care how students add fractions, as long as they can do it!

The advice for parts b and could be a lot shorter - say what's different from the previous part, how to deal with it, and then briefly show the working out.

#### Lauren Richards3 years, 2 months ago

Gave some feedback: Needs to be tested

#### Lauren Richards3 years, 2 months ago

Gave some feedback: Has some problems

#### Stanislav Duris3 years, 3 months ago

I haven't noticed any major problems with this question, but I thought about a couple of ideas for slight adjustments.

- If you want the student to do this question without a calculator, don't you want to perhaps tell them not to use it in the question statement? You mention not using a calculator in advice but not in the question itself. Also, you tell them to simplify their answer twice in the question statement. I don't know if you've done this on purpose so they are more likely to notice it, or if this was a mistake.

- Maybe you can slightly adjust a name of this question since there is some multiplication in part c). But it does mainly focus on addition/subtraction so if it stays like it is it should be fine.

- It's a good idea to include the original question at the start of each part in the advice, but maybe it would be even nicer to use the  format to display it? And maybe also all lines in advice consisting entirely out of equations could be changed into that format. This would make it look a bit neater, since this topic requires a lot of steps and it may be easy to get lost in.

- Although this isn't the question with a main focus on GCD and LCM and I am not sure how you would write this in advice, I still think more advice (maybe just 1 or 2 general sentences with an example different from a question that wouldn't be with variables) on how to find these would help students with simplifying fractions since I think that is the big part of the question. However, if you have included this in some of your other questions about fractions, this isn't essential.

- Also, in Advice at the end of each part you wrote "Using this value to simplify, the final answer is ...", maybe specifying you're dividing both numerator and denominator with this value would help someone struggling with simplification and can't see how it works clearly.

- You keep using the plural form of denominator when saying "keeping the denominators the same" - I don't know if this is better than just using a singular as this is when the two denominators merge into one.

- In the numerator part, the third line consists of just a fullstop from the previous line. I know this will probably differ depending on the device the student is using, but if this is the standard layout it would be great if you could try to fix this somehow. It's a silly thing but it may be distracting. If it's displayed differently on each computer, I'm sorry and I'll shut up.

- When the greatest common divisor is 1 and there is no simplification needed, the last line "Simplifying using...." doesn't really make sense, so it could be changed to be conditionally visible only if gcd ≠ 1, if you're not sure how to do that I can help. However, it can often be very laggy to work with this and Numbas sometimes crashes when you do this, so it's up to you.

Ultimately I think this question does the job well. Good job designing/defining all the variables cause it looks tricky.

#### Lauren Richards3 years, 3 months ago

I have enacted all the changes you suggested and particularly ensured that all the fractions in the question and advice will cancel down to their simplest form by making them all coprime.

#### Lauren Richards3 years, 3 months ago

Gave some feedback: Needs to be tested

#### Vicky Hall3 years, 3 months ago

Gave some feedback: Has some problems

#### Vicky Hall3 years, 3 months ago

This question has largely the same issues as the other fraction questions I have already commented on. Have a look through and check that:

1) You're using \displaystyle where necessary.

2) There are no unsimplified fractions in the questions.

3) There are no unnecessary colons in the advice.

#### Lauren Richards3 years, 3 months ago

Gave some feedback: Needs to be tested

#### Lauren Richards3 years, 3 months ago

Created this.
Addition and subtraction of fractions Ready to use Lauren Richards 20/11/2019 14:32
Jo-Ann's copy of Addition and subtraction of fractions Ready to use Jo-Ann Lyons 14/01/2019 15:43
surbhi's copy of Addition and subtraction of fractions draft surbhi gautam 14/01/2019 15:47
Nicolas's copy of Addition and subtraction of fractions draft Nicolas Sawyer 17/05/2020 10:53
Jose's copy of Addition and subtraction of fractions draft Jose Camarena Brenes 16/06/2020 19:05
Jose's copy of Addition and subtraction of fractions draft Jose Camarena Brenes 16/06/2020 19:14
Addition and subtraction of fractions Ready to use John Ian Keng 27/06/2020 06:59
Addisjon og subtraksjon av brøker draft Torris Bakke 23/06/2020 12:02
Addition and subtraction of fractions draft Ashley Cusack 31/08/2020 14:59
Addition and subtraction of fractions Ready to use Vicky Hall 21/09/2020 09:30
Ulrich's copy of Addition and subtraction of fractions draft Ulrich Görtz 16/09/2020 12:31
Ashley's copy of Addition and subtraction of fractions draft Ashley Cusack 16/09/2020 19:38

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