# What is the missing number in this wheel? What's the missing number? From World of Engineering.

• I'm not sure if I've followed the rules correctly, please let me know so I can edit the post. Oct 20, 2022 at 20:31
• This type of questions is not the best (similar to number sequences) if you do not know the simply explained solution. If you know the solution, some other tag would be desired (e.g. lateral-thinking or number sequence ...)
– z100
Oct 20, 2022 at 21:42
• I don't know the solution, should I change the tags? Or maybe simply delete the post if it's not appropriate for Puzzling. Oct 20, 2022 at 22:20
• There's no puzzle posted. You could post a link to any kind of published puzzle, but it is not a question. Oct 21, 2022 at 12:07
• Would it make sense to reformulate the post in some way? I'm really curious about how this problem is solved and I'm not sure how to ask for help. Should it be posted in a different forum perhaps? Oct 21, 2022 at 12:12

Firstly, may be useful to share that I found here World of Engineering the same puzzle with different numbers position!! Most of those "number in wheel" problem patterns are about the opposite/diagonal side, looking at the two examples below: That will be solved like this:

11:1x1=1 , 24:2x4=8 , 36:3x6=18, Then 13:1x3= 3

The second one is: That will be solved like this:

ALL Diagonal sum up to 24. 14+10 = 13+11 = 18+6, then 4+20 =24

## In our case

I solved like this:

So, the missing number is 7

.

• Beautiful answer! How about the other way around? 10^2 = 100, but 1 + 0 + 0 does not equal 8. Does it make sense to seek this kind of symmetry in these kinds of problems? Oct 22, 2022 at 10:28
• @Tsiolkovsky, Thanks for this note. It's really wired!! I think there is another logic for the 2nd one, maybe for example ( summing prim factor, or sum of divisors!) (1: have one divisor=1); (10: have 1,2,5 the sum will be 8); (9: have 3 two times, maybe 6); then 5 is a prime number, may the result is 1 Oct 22, 2022 at 11:40

the missing number is 2 because it looks like a double mirrored 5, and is the difference between 8 and 10. this is all wrong yet whatever.