Did you know that?
1 x 8 + 1 = 9
12 x 8 + 2 = 98
123 x 8 + 3 = 987
1234 x 8 + 4 = 9876
12345 x 8 + 5 = 98765
123456 x 8 + 6 = 987654
1234567 x 8 + 7 = 9876543
12345678 x 8 + 8 = 98765432
123456789 x 8 + 9 = 987654321
lol
Did you know that?
1 x 8 + 1 = 9
12 x 8 + 2 = 98
123 x 8 + 3 = 987
1234 x 8 + 4 = 9876
12345 x 8 + 5 = 98765
123456 x 8 + 6 = 987654
1234567 x 8 + 7 = 9876543
12345678 x 8 + 8 = 98765432
123456789 x 8 + 9 = 987654321
lol
Another one
1 x 9 + 2 = 11
12 x 9 + 3 = 111
123 x 9 + 4 = 1111
1234 x 9 + 5 = 11111
12345 x 9 + 6 = 111111
123456 x 9 + 7 = 1111111
1234567 x 9 + 8 = 11111111
12345678 x 9 + 9 = 111111111
123456789 x 9 +10= 1111111111
9 x 9 + 7 = 88
98 x 9 + 6 = 888
987 x 9 + 5 = 8888
9876 x 9 + 4 = 88888
98765 x 9 + 3 = 888888
987654 x 9 + 2 = 8888888
9876543 x 9 + 1 = 88888888
98765432 x 9 + 0 = 888888888
Brilliant isn’t it?
Now look at this symmetry:
1 x 1 = 1
11 x 11 = 121
111 x 111 = 12321
1111 x 1111 = 1234321
11111 x 11111 = 123454321
111111 x 111111 = 12345654321
1111111 x 1111111 = 1234567654321
11111111 x 11111111 = 123456787654321
111111111 x 111111111=12345678987654321
:laugh:
Brilliant, I’ve only seen the last one before!
Dear Rima,
That is sooo cool! I am math-challenged because here in America, they teach you only ONE method to solve problems and it is the longest method. I began to enjoy simple math equations in my head after my husband explained some simple tricks that he learned.
Being a visual learner - the equations you posted are very interesting to me.
Would you share your tricks, Ayesha?
Dear Nikolett & Everyone,
Little tricks like what are mentioned in this blog:
http://wildaboutmath.com/2007/11/11/impress-your-friends-with-mental-math-tricks/
I wish I had learned these in school.
That is cool. I learned some tricks but not like that.
This is mine: when you multiply 11 by a two digit number eg. 12 you take the two digits add them together (to get 3) then put that number in the middle of the first two (132)…simple huh.
11 x 10 = 120
11 x 11 = 121
11 x 12 = 132
11 x 13 = 143
11 x 14 = 154
11 x 15 = 165
11 x 16 = 176, etc…
Thanks Rima for the beautiful equations - they make me want to embrace something I’ve always if not feared, at least been uncomfortable with.
And Ayesha for the link - if I’m going to raise myself a quantum physicist, I’m going to need all the help I can get…
:biggrin:
i LOVE maths… in school I am the only one doing math… but its only cos I honestly enjoy doing math and it is not as difficult for me as its for my classmates… but i have one problem, I cant teach it! I just see sums and understand it but its hard to explain, there are times i dont need to do the work but can just get the answer… i dont know how or why or where I developed it!
but one thing, I hated calculators in school to do simple maths!
The simple 9 times is easy too
9 x 1 = 09
9 x 2 = 18
9 x 3 = 27
9 x 4 = 36
9 x 5 = 45
9 x 6 = 54
9 x 7 = 63
9 x 8 = 72
9 x 9 = 81
9 x 10 = 90
Thanks, Ayesha, k
Just to think about it, I am a math and physics teacher by education and knew less than third of those :mad: I think doing equations “straightforward” way was overemphasized with us
Here is a comprehensive web page including more than 600 Math Tips & Tricks.
http://mathforum.org/k12/mathtips/beatcalc.html
Hope you’ll enjoy
Rima
lol
I am more than enjoying, I am thrilled, bookmarked it, followed some links and will play 21 game with my kids tomorrow!
k again :biggrin:
That’s right Nikolett. I even teach Physics and Math too in college for a year.
I studied Engineering for 5 years. Why do I only know 2 of those 6 sets of equations posted? lol lol
Squaring a 2-digit number: XY
1- The last digit (units column): The Last digit of squaring the 2nd digit (Y), Keep the carry1 for step 2.
2- Next digit (tens column) : The last digit of multiplying the 1st digit (X) by the units of (2 x 2nd digit (Y)) and adding the carry1 in step 1, Keep carry2 for step 3.
3- First digit(s):
a- If Y is less than 5, Square the 1st digit (X) and add carry2.
b- If Y is greater or equal to 5, Multiply the 1st digit (X) by (X+1) and add carry2.
Hope it is not too confusing.
Rima
Dear Rima,
Huh? :blink: Can you show an example for the visual learners please?
Dear Ayesha & Everyone,
Here are two examples for squaring a 2 digits number:
Example 1: XY = 64
Example 2: XY= 97
Isn’t it easy !!!
Rima
Dear Rima,
Uhhh - perhaps it is easy for others to read and understand these instructions. :nowink: However, for me, I have to see each step on a blackboard to comprehend it. :wacko:
Thanks anyways.
I can understand the instructions,
just isn’t it simpler to multiply to numbers and get traditional square (XYxXY =) ? Maybe with practice it saves time…