Dan had 12 3/4yard of cable. He used 3 1/2yards for one computer and two more cables of 2 7/8 for two other computers. He needs 3 1/3yard for the last computer.

a. Does he have enough?
b. If not, how much more does he need?
c.If so, how much does he have left?

Add: 3 1/2 + 2 7/8 + 2 7/8 + 3 1/3 = ?