Community Chat

[Mary Bailey]

wow! amazing

[cbrite]

No....I do not know what numbers those are. 

I did it twice....Have no idea.

[Lucky Charm]

Nope, did it with 3 different phone numbers

***did it again and got it!***

Edited days later!!!

[GrailSeeker]

It came out right for me.

[cbrite]

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@Lucky Charm wrote:

Nope, did it with 3 different phone numbers.

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I had to use the calculator ON the phone to achieve the right answer... I could not use any calculator. My first attempt for my land line went no where.... so I used my tiny mobile phone's calculator with it's own phone number and got the right answer. Remember to do the = sign after each entry. 

It was correct.....

............ETA....I was wrong again....any calculator will work.....it's the = sign after each entry that is crucial..... to arrive at the answer. 

(cb slinks away as official thread killer) 😬☹︎

[GrailSeeker]

Here is a another cool math trick.  My dad taught me this, never heard it in school.  Maybe you can pass it on to your children/grandchildren.

A little boy was given this quiz for multiples of 9 at school:

2 x 9 =

3 x 9 =

4 x 9 =

5 x 9 =

6 x 9 =

7 x 9 =

8 x 9 =

9 x 9 =

Realizing that he did not know any of the answers, he counted them to see how many questions he was going miss:

2 x 9 = 1

3 x 9 = 2

4 x 9 = 3

5 x 9 = 4

6 x 9 = 5

7 x 9 = 6

8 x 9 = 7

9 x 9 = 8

Eight wrong answers!  That seemed like a lot, so he decided to count them again, this time from the bottom up, just make sure:

2 x 9 = 18

3 x 9 = 27

4 x 9 = 36

5 x 9 = 45

6 x 9 = 54

7 x 9 = 63

8 x 9 = 72

9 x 9 = 81

He turned in the quiz as is and got 100% A+!

The other cool thing about multiples of "9" is that the numbers in the correct answer always add up to 9!

2 x 9 = 18  (1 + 8 = 9)         

3 x 9 = 27  (2 + 7 = 9) 

4 x 9 = 36  (3 + 6 = 9)

6 x 9 = 54  (5 + 4 = 9)

7 x 9 = 63  (6 + 3 = 9)

8 x 9 = 72  (7 + 2 = 9)

9 x 9 = 81  (8 + 1 = 9)

Bookkeepers trick:  if your calculator tape is off by "9" or a multiple of 9, it is often due to a transposed number (for instance, entering 89 instead of 98 - the difference between a transposed number is always "9", or a multiple of 9 (98 - 89 = 9;  42 - 24 = 18; 97 - 79 = 18; 150 -105 = 45; 170 - 107 = 63)

[CANDLEQUEEN]

Wow! very cool!

[stevieb]

Very neat, both of them. I always wished I'd 'got' math instead of struggling along to fulfill requirements... It would be nice to be able to figure out and to understand why things like this work out... 

[Lucky Charm]

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@cbrite wrote:

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@Lucky Charm wrote:

Nope, did it with 3 different phone numbers.

---

I had to use the calculator ON the phone to achieve the right answer... I could not use any calculator. My first attempt for my land line went no where.... so I used my tiny mobile phone's calculator with it's own phone number and got the right answer. Remember to do the = sign after each entry. 

It was correct.....

............ETA....I was wrong again....any calculator will work.....it's the = sign after each entry that is crucial..... to arrive at the answer. 

(cb slinks away as official thread killer) 😬☹︎

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@cbrite Thanks!  I had edited my post to say that I did do it again and *it worked*.  But I guess my edited post didn't go thru.  Thanks!