Question

A rope has a density and thickness such that a 3.25-centimeter-long segment of it weighs 61.40 grams. There are 28.3495 grams in an ounce and 2.54 centimeters in an inch. How many ounces would a 19.45 inch length of the same rope weigh?
a.
5.10 oz
b.
11.49 oz
c.
32.92 oz
d.
53.90 oz

Answer 1

Weight per cm = 61.40 g / 3.25 cm = 18.8923077 g/cm.
19.45 in = 19.45(2.54) = 49.403 cm.
Mass = 18.8923077 g/cm × 49.403 cm = 933.3442 g (actually 3033.3442? Wait check) — better compute in one fraction:

oz = (61.40 g / 3.25 cm) × (19.45 in × 2.54 cm/in) ÷ 28.3495 g/oz
= 3033.3442 / 92.135875 ≈ 32.92 oz.

Answer: c. 32.92 oz.