In order to rewrite the expression using addition, you would change all the subtraction signs and make the second terms negative. This means that your new expression is 2 + -2 1/4 + 3 2/5. If the number is already negative, the second negative sign would make it positive. Once you've got Part A done, do 2 + -2 1/4 which would give you -1/4. Then you add -1/4 and 3 2/5 by finding common denominators, 20. -5/20 + 3 8/20 would give you 3 3/20 as your final evaluated answer.