The sum of x and 3/5 is 5/7.

What is the value of x?

Enter your answer in the box as a fraction in simplest form.

x = ?

We first write the word in math as x+3/5 = 5/7. Now we cross multiply our fractions and rewrite them with the LCD of 5 and 7. Our equation now looks like x + 21/35 = 25/35. We simplify our equation by subtracting 21/35 from both sides to get x = 4/35. 4/35 is already in lowest terms so it is our answer.