A multinational firm wants to estimate the average number of hours in a month that theiremployees spend on social media while on
the job. A random sample of 83 employees showedthat they spent an average of 21.5 hours per month on social media, with a standard deviationof 2.5. Construct and interpret a 95% confidence interval for the population mean hours spenton social media per month.
2 answers:
Answer:
95% of the population spent between 16.8 hours to 26.2 hours on social media per month
Step-by-step explanation:
- subtracting 1 from sample size: 83-1= 82
- Note Mean=21.5 and standard deviation=2.5
- Subtracting confidence interval from 1 and dividing by 2: (1-0.95)/2=0.025
- At α=0.025 and dF=82, the t-distribution table gives 1.984
- Divide standard deviation by square root of sample size: 21.5/√83= 2.36
- Multiplying answer in step 4 by answer in step 5: 2.36×1.984= 4.68
- For lower end: 21.5-4.68= 16.82
- for upper end: 21.5+4.68=26.18
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