Brain Teasers
400, 361, 324, 289, 256, 225...
400, 361, 324, 289, 256, 225...
Which number comes next?
Which number comes next?
Answer
196.They're square numbers: 20*20, 19*19, 18*18, 17*17, 16*16, 15*15, ... we're looking for 14*14.
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Comments
Very fun, very easy.
I got 196, but did it this way....
(-39, -37, -35, -33, -31, -29.....)
Math rule?
(-39, -37, -35, -33, -31, -29.....)
Math rule?
Yep that is a math rule
squares starting from 1 increase
by 3, then 5, then 7, etc.
Here's why:
123456
223456
333456
444456
555556
666666
Each number represents what you have to add to get the next square. For example, to get to 4 squared, you have to add 7 to the 3x3 square.
Now, take them apart:
_____________4
_______3_____4
___2___3_____4
1 22_333_4444
As you can see, you add 1 to the top and left to make the next one. This is why you add 2 to each difference value.
I apologize for writing an unneccesarily long comment.
squares starting from 1 increase
by 3, then 5, then 7, etc.
Here's why:
123456
223456
333456
444456
555556
666666
Each number represents what you have to add to get the next square. For example, to get to 4 squared, you have to add 7 to the 3x3 square.
Now, take them apart:
_____________4
_______3_____4
___2___3_____4
1 22_333_4444
As you can see, you add 1 to the top and left to make the next one. This is why you add 2 to each difference value.
I apologize for writing an unneccesarily long comment.
Thanks for the math lesson, Calmsavior. I learned something new!!
You might as well have been speaking Japaneese.... Informative though!
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