If you have two numbers,that are different ie,12 then you turn it round,21, take the lower number away from the higher number ,why does the answer always work out as 9 whatever two number you chose?
Question asked by: knowitall
This doesn't always work, for instance 33 reversed is 33.
If the difference between the digits is 1 then this works simply because of the non-trivial fact that x - y is (x - 10) + 1 therefore the reversal is mimicking this fact.
By: Unknown
Average rating for this answer is 2.5 / 5
Rate Answer
Comment or provide your answer to this question
No comments have been added to this question "If you have two numbers,that are different ie,12 then you turn it round,21, take the lower number away from the higher number ,why does the answer always work out as 9 whatever two number you chose?".
No comments have been added to this question "If you have two numbers,that are different ie,12 then you turn it round,21, take the lower number away from the higher number ,why does the answer always work out as 9 whatever two number you chose?".
Ask a New Question
Find out more about Maths
Find out more about Maths
Maths Questions and Answers
maths school questions Questions and Answers
Next question: if the answer of the sum is 1000 and you can only use 88888888 how do you work this out?
Become a Member! It's Free >>>
Share on Facebook: 
On Twitter:
Tweet this!
Question Keywords
higher chose always numbers round lower
More Questions:I Am The Smallest Number That Is Both A Square And A Cube What Number Am I
Number Sequences Help Please
If Rayan Drives 2 Hour 60km And Rohan Drives 30 Km What Is The Ratioof Rayan To The Ratio Of Rohan
List Degrees Of An Acute Angle
Find The Number Of Big Boxes Sold