Did you get 5000? Good job but the answer is actually 4100. Written as below it is perhaps easier to figure out:
1000 + 40 + 1000 + 30 + 1000 + 20 + 1000 + 10 = 4100.
Exercising the brain since 2017
We really love this mental number challenge.
You must do this in your head do not use paper or a calculator!
Take 1000 and add 40 to it.
Now add another 1000 to it.
Now add 30.
And another 1000.
Now add 20.
Now add another 1000.
Finally now add 10.
What is the total?