Very tricky math!

Note: This must be done in your head only. Do NOT use paper and pencil or a calculator. Try it.

Do not peek at the bottom of the blog.

Hey! I said...DO NOT peek...why'd you look??? Oh well, try it anyway.

Take 1000 and add 40 to it.

Now add another 1000.

Now add 30.. add another 1000.

Now add 20.

Now add another 1000.

Now add 10.


What is the total?


5000?

5100?

4100?


Actually, it's 4100.