Question

The advertised claim for batteries for cell phones is set at 48 operating hours, with proper charging procedures. a study of 5000 batteries is carried out and 15 stop operating prior to 48 hours. do these experimental results support the claim that less than 0.2 percent of the company's batteries will fail during the advertised time period, with proper charging procedures? use a hypothesis-testing procedure with the proportion of cell phone batteries that fail

Answer 1

Answer:

The answer is NO. The experimental results did not support the claim that less than 0.2 percent of the company's batteries would fail during the advertised time period.

Explanation:

From the illustration, for 15 batteries to fail out of 5000 batteries that means a 0.3 percent failure. Hypothetically, since there has been a claim that about 0.2 per cent will fail and we now have a confirmed failure rate of 15 in 5000 or 0.3 per cent rate, then we can infer that the hypothesis of 0.2 percent may be incorrect after all since it is still less than the confirmed rate of 0.3 per cent failure. Thus, since 0.3 rate is higher than 0.2 rate, then the hypothesis is wrong by a margin  of 0.1 percent.