Australia. She’s in year 5, 11 in December.

They give out Problems of the Week, which have one ‘Easy’, one ‘Medium’, one ‘Advanced’ and occasionally one they call ‘Genius’. This one was under the latter but not as challenging as some other types I’ve seen (which required one to recognise patterns; what is the value of the ones digit in 123^19 etc).

Typically the problems are asking students to use bar models to solve problems. The bar model came well after my school days, so I’m teaching her to use variables and solve as simultaneous equations. Hopefully I’m not doing her harm!

I took another look at the Q and the wording is worse than in conveyed...

Fiction, Comic and Science and Technology.

Don’t tell me there’s 4 types of books!

Probability questions are “what are the odds” type questions.

Think deck of cards. 4 of 52 chance you will pick an Ace. 4/52 = 1 in 13 chance

So, no.... the answer is not 2, 7, or 42... or others hat have responded.

I assume you will be told what the expected answer is?

Please post it here with the explanation (if provided) so we can grade the teacher. :)

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"...the street finds its own uses for things"

If you're approaching it as a probability question the answer doesn't change. That's the beauty of maths, you can take multiple approaches to arrive at the same answer.

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Swimming Workout of the Day:

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2020 National Masters Champion - M50-54 - 50m Butterfly

What are the odds of dying from Covid 19? 7

No. You could say, 7 of 1,000

Which would be 7/1000, or .007%


The answer needs to be a ratio which can be converted to a percentage.

In this case people who said 7, should say 1 in 7 or, 1/7= 14%

14% of what?

the question specifically asked "how many kids", essentially, how many kids need to pick books before the probability of 2 kids selecting the same types of books equals 1. 14% is not a valid answer, nor is 1 in 7. The answer must be an integer.

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Swimming Workout of the Day:

Favourite Swim Sets:

2020 National Masters Champion - M50-54 - 50m Butterfly

the odds approach is a different question, and would be worded what is the probability that the 3rd student pick 2 books the same two categories as either student 1 or 2. However this question is what is the number of student that can pick 2 types of books where the probability is 100% that at least 2 students have chosen the same two categories... these are different questions one is to determine the probability, and the other is the opposite they have given you the probability you need to determine the number. Still fun to see how people approach a somewhat ambiguous question and the answers given. I agree with Jasoninhalifax math is math the answer will be the same no matter how you do it, but this is where the wording comes into the problem it is really an issue of a grammar problem not a math problem.

While I am a staunch proponent of the oxford comma, the lack of one here does not add any ambiguity to the question.
The question doesn't say "Fiction, Comic and Science and Technology" it says
"Fiction, Comic and Science & Technology"

The "&" is being used to differentiate between items on a list, and items that are grouped together to form a single item.
Yes, the Oxford comma should almost always be used but, in this case it is not necessary to positively identify this as a list of 3 items, one of which is "Science & Technology"

This whole thread has been a wonderful example of people not understanding the meaning of words and phrases in the context in which they are being used, and complaining that it is a badly written question. Interesting to see people immediately jump to the conclusion that, something is wrong with the question, rather than their own understanding of what the question means.

"Which would be 7/1000, or .007%"


0.7%.

Thank you

Brain fires at 40% at 6:55am

What, you can’t have 14% of a kid?

I read the question again. I’m wrong, in this case. They do specifically ask “How many kids”.

Except that the question emailed to students says “Fiction, Comic and Science and Technology”

I did not realise that when writing post #1 I provided my interpretation of the question’s intent. My daughter was getting upset with me last night as she was adamant it meant four book types.

The primary uncertainty for me was whether the question should assume everyone borrows two books or whether one/none is an option.

It’s s pupil free day here today. I’ll get my daughter to email the teacher for clarity then return to put this one to bed.

 

Nah. It's good for kids to see multiple solution methods.

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maybe she's born with it, maybe it's chlorine
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