The marking of this maths homework had people bellowing into next week
Another day, another example of maths homework marking to get you all worked up. Here’s the question and teacher’s answer as shared by Math Lady Hazel over on Twitter.
I can’t believe my eyes. pic.twitter.com/0cQhZBtyey
— Math Lady Hazel (@mathladyhazel) December 19, 2023
Just in case that’s tricky to see in full …
And with that post, the cat was well and truly put amongst the pigeons.
Some people saw no problem with the teacher’s marking…
10 minutes divided by 2 pieces = 5 minutes per piece
3 pieces x 5 minutes = 15 minutes
I don’t see an issue with the answer…
— Sebastian (@Sebastian_707_) December 20, 2023
But they were quickly given clarification –
It’s by cut not by piece. One cut requires 10 mins, two requires 20. The formula would be (n-1)*10.
— Joe Welch (@JoeWelch894180) December 20, 2023
Other people thought teacher was correct but for a different and perhaps more dubious reason (and it’s probably just an example of trolling) –
No, 15 minutes is actually the right answer. You learn more about cutting after each cut and get twice as fast each time. So:
– 1 cut takes 10 minutes
– 2 cuts take 15 minutes
– 3 cuts take 17.5 minutes
– You can make ALL the cuts in 20 minutes
That’s just science.
— Andrew Stellman (@AndrewStellman) December 19, 2023
But it turns out that there are other ways in which the teacher could legitimately be correct and some people provided graphics to demonstrate…
No, 15 minutes is actually the right answer. You learn more about cutting after each cut and get twice as fast each time. So:
– 1 cut takes 10 minutes
– 2 cuts take 15 minutes
– 3 cuts take 17.5 minutes
– You can make ALL the cuts in 20 minutes
That’s just science.
— Andrew Stellman (@AndrewStellman) December 19, 2023
15 minutes is correct for a quadratic board with side length a.
The first cut is length a and takes 10 minutes.
The second cut is length a/2 and takes (approx.) 5 minutes.
The third cut is length a/2 and also takes 5 minutes.
[Of course, the board in the test did not seem to… pic.twitter.com/jUpRGiuQEc— (@Velofisch) December 20, 2023
So the only thing we’ve learned for certain is that maths is hard and confusing and probably not worth thinking about.
