Question

Evaluate (66600731427)(66600731417) - (66600731437)(66600731407) (No calculator!)

Answer 1

what about wolframalpha

Answer 2

No tools or anything. Just paper and pencil.

Answer 3

ummmmm... pass

Answer 4

(66600731427)(66600731417) - (66600731437)(66600731407)
Let 66600731407=x
so we have
\[(x+20)(x+10)-(x+30)(x)\]
\[x^2+30x+200-x^2-30x\]
\[200\]

Answer 5

lol, I like this one.

Let \(a=66600731427\)
\[a(a-10)-(a+10)(a-20)\]
\[a^2-10a-(a^2-10a)=0\]

Answer 6

i was afraid of doing this because of the number 666..

Answer 7

OOH, forgot! 200!

Answer 8

@dpaInc no. of the beast

Answer 9

\[(a^2-10a-(a^2-10a-200)=200\]

Answer 10

Oh! I get it. I didn't think of using variables in this situation! Thanks everyone! It is 200!

Answer 11

yep....

Answer 12

@Calc, you can always use variables. It helps you understand the relationship between the quantities.

Answer 13

nice problem @Calcmathlete ....:)

Answer 14

I meet be having a few more tonight :)