Make this without a calculator

This Simple Math Problem Keeps Stumping People

An additional problem that seems easy enough at first glance is being widely shared, as people’s mental arithmetic skills keep getting tripped up by the same part of it. All you have to do is add up the following numbers. Try it for yourself:

You have 1000,

add 40,

add 1000,

add 30,

again add 1000,

add 20,

again continue reading …