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What if the first number is odd?
For example: 15^2 + 30^2
15^2 + 30^2 equals 1125. You just follow the same trick, so 15^2 is 225, and you divide 225 by 2, yielding 112.5, and you multiply that by 10. I think Mr. Gillespy meant that adding the zero means multiplying by 10.
Exactly. Adding zero means times 10.
What would you do in the approximate question like 14^2+48^2. Thanks
The type of question usually has a pattern like 2 times 3 times or 7 times as big are you sure its not one of those?
So what do I do if the question has the units digits add up to ten and tens digits are the same? For example: 63^2+67^2
By the blue book its all in there.
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8 comments
Skip to comment form
What if the first number is odd?
For example: 15^2 + 30^2
15^2 + 30^2 equals 1125. You just follow the same trick, so 15^2 is 225, and you divide 225 by 2, yielding 112.5, and you multiply that by 10. I think Mr. Gillespy meant that adding the zero means multiplying by 10.
Author
Exactly. Adding zero means times 10.
What would you do in the approximate question like 14^2+48^2. Thanks
Author
The type of question usually has a pattern like 2 times 3 times or 7 times as big are you sure its not one of those?
So what do I do if the question has the units digits add up to ten and tens digits are the same? For example: 63^2+67^2
Author
By the blue book its all in there.