This simple maths puzzle is confusing everyone – and you’ll probably get it wrong
A MATHS puzzle is causing mass confusion on Twitter as people can't seem to agree on the answer.
The seemingly simple equation has gone viral with over 34,000 retweets at the time of writing.
The maths puzzle was posted to Twitter by user KJ Cheetham who said: "A maths meme that is actually funny rather than stupid: 230 - 220 x 0.5 ="
He then proceeded to say that the answer was "5!" but lots of people think that the answer is actually 120.
The tweet sparked so much debate that the original tweeter had to mute the notifications he was receiving from it.
The trick is actually to do with how KJ Cheetham typed out the answer because lots of people don't realise that when an exclamation mark is used in maths it can change the value of a number.
Therefore the answer isn't really five at all because "5!" actually equals 120.
This is because the exclamation mark represents the factorial meaning the number next to it will then be multiplied by all the numbers below it.
In the case of the number five this would mean it would be multiplied by four, three, two and one.
So the lesson here is that the answer is actually 120 and Twitter users should have been more careful of the phrasing of the original perplexing tweet as that is where the real trick lies.
What's the solution?
Here is how to work it out...
- An "!" symbol next to a number can mean multiplying that number by all the numbers below it
- In this case 5! = 5 x 4 x 3 x 2 x 1 = 120
- 230 - 220 x 0.5 also gives an answer of 120 so in this case no one was wrong, the answer had just been written down in two different ways
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And, what do you think the answer is? Let us know in the comments!
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