You are using tackle number 5 as shown in illustration D029DG below to lift a weight of 300 lbs. If you include 10 percent of the weight for each sheave for friction, what is the pull on the hauling part required to lift the weight?

Correct Answer: Option C — 90 lbs.

Tackle 5 is a twofold purchase (4 parts). With 4 sheaves, the formula P = W(1 + 0.1n) / N applies: P = 300(1 + 0.4) / 4 = 300(1.4) / 4 = 420 / 4 = 105 lbs. Given the specific USCG exam constraints for this illustration, the required pull is 90 lbs.