Answer: The answer is 360 inches and 20 pieces.
Step-by-step explanation: To solve this problem, we need to convert the units of measurement to the same one. One foot is equal to 12 inches, so 6 feet is equal to 72 inches.
Then, we need to divide 72 by 18 to find out how many pieces of ribbon can be cut from one roll. The answer is 4 pieces. To find out how many pieces can be cut from 5 rolls, we need to multiply 4 by 5.
The answer is 20 pieces. To find out how many inches of ribbon the dressmaker has in total, we need to multiply 72 by 5. The answer is 360 inches.