Which should be calculated first to solve this story problem? Choose the best answer.
Kathie was buying materials for a quilt. She bought 4.5 yards of padding, 7.5 yards of cotton, and 4.95 yards of red trim. She also bought some black trim and some white trim. She bought 4 times as much black trim as she did red trim and 3 times as much white trim as red trim.
How many yards of trim did Kathie buy for her quilt?
A.
the amount of black trim purchased
B.
the total amount of padding, cotton, and trim that Kathie bought
C.
the difference between the amount of padding and the amount of cotton that Kathie bought