How to turn 0.4 into fractions

Think about it this way: 0.4 is read as what?

It's read as "four tenths".

This means that it can also be said as "four out of ten".

So, 0.4 into a fraction is "4/10".

Now, this fraction can be reduced, so what is the greatest common factor of 4 and 10?

Factors of 4: 1,2,4

Factors of 10: 1,2,5,10

So the greatest common factor is 2.

So, if you divide both 4 and 10 by the greatest common factor to get (4/2) = 2 and (10/2) = 5.

So, the reduced fraction would end up being 2/5.

When you divide 2 by 5, you get 0.4, if you want to check.