So the first thing to remember is that the 4 on the mixed number is a whole number and will still be whole in the decimal. That is to say that it will be in front of the decimal. Now, to turn a fraction into a decimal, you can either divide the numerator by the denominator or put it over 10, 100, 1000, etc. So I will show you how to put the fraction over ten.
2/5 x 2/2 = 4/10
So now you put the 4 into the tenths place of the decimal, or .40. Then add the whole number to the front, and you get 4.40 as the answer.
Hope this helps, if you still have questions please comment! :)
