A Population Proportion · Exercise 11

Of 1,050 randomly selected adults, 360 identified themselves as manual laborers, 280 identified themselves as non-manual wage earners, 250 identified themselves as mid-level managers, and 160 identified themselves as executives. In the survey, 82 percent of manual laborers preferred trucks, 62 percent of non-manual wage earners preferred trucks, 54 percent of mid-level managers preferred trucks, and 26 percent of executives preferred trucks.

Suppose we want to lower the sampling error. What is one way to accomplish that?

Its source prints no answer for this problem, so there's nothing to check against.

OpenStax, Statistics · §8.3 A Population Proportion · Exercise 11