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### History and Feedback

#### Checkpoint description

Describe what's changed since the last checkpoint.

#### Christian Lawson-Perfect2 years, 2 months ago

Saved a checkpoint:

I've split each part into a separate question.

#### Christian Lawson-Perfect2 years, 2 months ago

Gave some feedback: Should not be used

Published this.

#### Elliott Fletcher2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Elliott Fletcher2 years, 2 months ago

Gave some feedback: Has some problems

#### Aiden McCall2 years, 2 months ago

Question:

Needs a comma between outcomes and you. "For equally likely outcomes, you can..."

I would personally change 'happening' to 'occuring'.

I would also change 'So' to 'Therefore'.

Change 'Let's say' to 'If'.

The question with the example does seem quite wordy. I was wondering if you would be able to reduce the words by having a table for the line starting "We roll a...".

I don't think you need a comma after "fair" in "fair 6-sided die". I would then place the comma as follows, "fair 6-sided die, we are equally..."

I also don't think you need a comma after 'Hence'.

For c) I would add another answer with the same numerator but different denominator. This is because you do not have to calculate the probability but just look for the numerator with the same value as the blue balls. I understand that in the cases of simplification this may not be the case, but I think these occur less often then not.

a) i) "Now we must think how many outcomes are there that result in an even number being rolled." I would remove are there that so it reads as follows.
"Now we must think how many outcomes result in an even number being rolled.

c) "As the ball is being selected randomly from the bag, there is an equal probability of selecting a ball which is any of the 3 colours."

I am not sure this statement is true or at least reads such that, there is an equal probability of selecting any of the 3 colours when the probabilities for the selection of the three colours are different.

#### Elliott Fletcher2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Chris Graham2 years, 2 months ago

As discussed, it would be nice to have an example in the statement.

#### Vicky Hall2 years, 2 months ago

Gave some feedback: Has some problems

#### Vicky Hall2 years, 2 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.

#### Elliott Fletcher2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Elliott Fletcher2 years, 2 months ago

Created this.
Basic Probability Questions Should not be used Elliott Fletcher 25/07/2017 15:08
Choose the probability of getting certain scores on a die Ready to use Christian Lawson-Perfect 01/08/2017 13:27
Probability of flipping a coin and getting a tails Ready to use Christian Lawson-Perfect 01/08/2017 13:26
Probability of picking a particular colour ball from a bag Ready to use Christian Lawson-Perfect 01/08/2017 13:26
Maria's copy of Choose the probability of getting certain scores on a die draft Maria Aneiros 27/05/2019 02:29
Maria's copy of Probability of picking a particular colour ball from a bag draft Maria Aneiros 27/05/2019 02:32
Choose the probability of getting certain scores on a die draft Xiaodan Leng 11/07/2019 01:57
Probability of flipping a coin and getting a tails draft Xiaodan Leng 11/07/2019 01:58
Probability of picking a particular colour ball from a bag draft Xiaodan Leng 11/07/2019 01:58

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