Let's write 0.8 as a fraction. So 0.8... the 8 right over here is in the tenths place. It is the tenths place. So you can read this as 8 tenths and we can write that literally as being equal to 8 tenths or 8 over 10. And now, we've already written it as a fraction and if we want we can simplify this down. Both 8 and 10 share common factors, they are both divisible by 2. So lets divide both the numerator and the denominator by 2. We are not changing the value of the fraction because we are dividing both the numerator and the denominator by the same thing 8 divided by 2 is 4, 10 divided by 2 is 5 and we're done. 0.8 is the same thing as 8 tenths, which is the same thing as 4 fifths.