A manufacturer samples 100 wires for quality testing. Four of the wires are found to be defective. If 750 wires are produced in one hour, how many should the manufacturer expect to be defective?

A. 30
B. 60
C. 75
D. 96

We can set up a proportion to solve for the expected number of defective wires:

Number of defective wires / Total number of wires sampled = Number of defective wires in 750 wires produced / Total number of wires produced

Using the information given, we have:

4/100 = x/750

Cross-multiplying, we get:

100x = 4 * 750

Simplifying:

100x = 3000

x = 30

Therefore, the expected number of defective wires in 750 wires produced is 30.

Answer: A. 30