@stevekerp1
Choose numbers X and Y and follow the procedure for a generalized formula. The seventh number is 5X + 8Y and the total of all numbers is 55X + 88 Y for any values of X and Y. Clever.
@gcewing
Mathematician: "Write down any two numbers." Audience member: "Any two? Really?" Mathematician: "Yes, anything you want." Audience member: Writes down g64 and TREE(3).
@DanDart
Initial thoughts: is this going to be like a bigger version of the 2n-2 trick? 2:20: is it gonna be the fibonacci trick Grime showed us? 3:53 fibs confirmed
@willjohnson8446
9:26 The first digit is not always the first digit — simply because there may be a remainder when adding the first digit to the second. This is why you should work it right to left — not left to right.
@michelemoneywell8765
This could be a great activity for a substitute teacher. The students will be impressed with the teacher. They could work together. They will be doing math. You can divide the class into small groups, have each do their 10 lines on different places on the white board while you relax. Or on paper at their desks, then transfer to the white board. (Good idea to have predrawn lines.) It's hands on, uses a good chunk of time, is impressive, and is interesting.
@eddabrandes7395
Why are some of you so mad? If the explanations are boring for you, just speed the video up. You chose to watch it, right? It's not as if your boss is ranting your brain to pieces but you can't show it or just leave. THAT is torture.
@lschwa01
If the sum of a set of 2 digits exceeds 9, the "write it down" method fails. However, the (X*10)+X will always work and it is easy to do in your mind..
@drdel76
My “da-da” moment failed because one of my audience added up his pair of numbers wrongly! I advise getting someone to check the arithmetic before “memorising” the numbers.
@G.L.Banning
Might be the coolest math 'trick' I've ever seen. Loved the connection to the Fibonacci sequence.
@johnkneelad
Excellent video.
@stephcats20
This is so cool. It's impossible to say how much I love numbers.
@st-lucia
That's good math!
@mathgenius199-i4h
tysm this vid was rly clear and easy to understand 😊
@47AndyT
I' ll have to check it out!
@HenrySimiyu-c3s
If u're my teacher at high school.....
@gigachadkartik
If first number is :x and second y then sum is 55x+88y and 7th number is 5x+8y
@LarueMasse-p3k
This was super clear and easy to understand!
@Manya_Singh7
Best thing I have done in my life is subscribing your channel Love your content
@kush-6891
It’s pure math. X+ 2X + 3x + 5x+ 8x + 13x + 21x + 34x+ 55x + 89x = 231x, which is 11 times 21x
@WrathofMath