Classic brain training methods are perhaps puzzles like crosswords or sudoku, but in recent times, I have become more and more attracted to the type of challenge you’ll see below.
These types of puzzles have been flooding the web lately, probably because they are really fun!
These are old classic mathematical problems. When you were in middle or high school.

These tests are more fun when you find yourself trying to remember the math you learned as a child.
Can you solve this equation – without a calculator?
Okay, now to the challenge.

Below is a tricky equation. Can you solve it without using a calculator?

What do you think the right answer is?

Hmm, now how did this work again?

Think long and hard, and you might be able to remember!

What do you think the right answer is?

The answer is written underneath this image.

A

B

C

ANSWER:

Follow the order of operations: multiplication first.

1×0=0

So the expression becomes:

9+1+9+0+1

Now add:

9+1=10
10+9=19
19+0=19
19+1=20

Answer: 20

Did you solve it?