Final answer:
Option D is the correct sequence for the pipes' lengths from longest to shortest: 19 1/2 in., 18 3/4 in., 18 1/2 in., 18 3/8 in. It lists the pipes' measurements in descending order, correctly comparing whole numbers and fractional parts.
Step-by-step explanation:
The question is asking for the correct order of pipes from longest to shortest based on their length in inches and fractions of an inch. To arrange the lengths in the correct order, you need to compare the whole numbers first, followed by the fractions. Inches represented as whole numbers with fractions demonstrate mixed numbers, which are vital in the plumbing industry to ensure precision in measuring items such as 4-inch pipe, 8-inch pipe, and 16-inch pipe.
The longest pipe mentioned is 19 1/2 inches, and none of the other measurements have a whole number larger than 19. Next are the measurements with whole number 18, which must be sorted by their fractional parts. The fractions in descending order are 3/4, 1/2, and 3/8 of an inch. So, the order from longest to shortest is 19 1/2 in., 18 3/4 in., 18 1/2 in., 18 3/8 in.
Therefore, the correct answer is Option D: 19 1/2 in., 18 3/4 in., 18 1/2 in., 18 3/8 in.