In this question, you are given a fraction number and asked the number form in decimal. The decimal form will make the number easier to add since it will have the same denominator like the tenth, hundredth, thousandth, etc.
To answer this question, you just need to divide 13/20 then add it with 4. The calculation would be: 4 + 13/20= 4+0.65= 4.65
