Ross needs to have a procedure done, and since he is over 65 he is on medicare. medicare says that according to their plan the allowed amount is 7/ 8 of what the doctors office charges. of that allowed amount they will pay 3 /4 and ross will be out of pocket 1 /4 . if ross had to pay $262.50, how much did the office want to charge for the procedure?
usa test prep answer is x=$1,200

Statements reasons 1. ab ? cd; ad ? bc 1. given 2. ac ? ac 2. reflexive property 3. ? adc ? ? cba 3. ? 4. ? dac ? ? bca; ? acd ? ? cab 4. cpctc 5. ? dac and ? bca are alt. int. ? s; ? acd and ? cab are alt. int. ? s 5. definition of alternate interior angles 6. ab ? cd; ad ? bc 6. converse of the alternate interior angles theorem 7. abcd is a parallelogram 7. definition of parallelogram what is the missing reason in step 3?