Question

A technology company determined that an average of 3 phones were defective for every 200 phones it produced. At this rate, about how many phones were defective if the company produced 50,000 phones?

Answer 1

You have to calculate the probability for the given average:
 = 3/200 = 0.015 = 1.5%
For 50,000 phones you have to multiply the probability by 50,000:
0.015*50,000 = 750 phone defectives if the company produced 50,000