Do the decimal first:
Every fraction is a short way to write a division problem.
A fraction means (the top number) divided by (the bottom number).
2/5 means '2' divided by '5' .
When you do that division, you get 0.4 .
That's the decimal equivalent of 2/5 .
Now you need to know how to turn a decimal into a percent.
It's easy. Just take the decimal, and move the point 2-places to the right.
0.4 = 40% .
