Poll

Did you get 5?

Yes
No

Author Topic: Fun trick  (Read 650 times)

Think of a number. Any number. Multiply it by two, add 10, divide it by two, and subtract it by the origional number. Is it:
5?
Post whether you got 5 or not.
Example equation:
65
65x2=130+10=140/2=70-65=

That's not impressive
and 140/2 does not equal 70 - 65

That's not impressive
and 140/2 does not equal 70 - 65
140/2=70
70-65
Its an on-going equation.

By multiplying by two and then dividing by two you aren't doing anything different, so that cancels out.
Adding 10 and subtracting by original will always get you 5 by doing the steps properly.


I did this in 4th grade in a reading group.

I got 9
My number was -2

You should have said pick any positive whole number

I got 9
My number was -2

You should have said pick any positive whole number
I feel dumb...
Not because I spent 15 minutes trying to plug in my mouse before I realized it was upside-down.
I just feel dumb.
and I KEEP trying fell instead of feel.