When turning a fraction into a decimal, any whole numbers comes before the "." and the fraction will become after the ".".
To make it simple, turn the fraction into a "over 100" fraction to make it easier.
Multiple both numeriator and denominator by a specific number, to turn the denominator into a 100. You must times the numeriator as well since your changing the denominator.
100 / 5 = 20
So now, multiple both sides of the fraction by 20.
3 x 20 = 60
5 x 20 = 100
2 60/100
Now, put the whole number in front of the decimal symbol.
2.___
Now, take the numeriator and put it behind the decimal symbol.
2.60
So, when turning 2 3/5 into a decimal, it is 2.60.