Question

The Bureau of Labor Statistics’ American Time Use Survey showed that the amount of time spent using a computer for leisure varied greatly by age. Individuals age 75 and over averaged 0.25 hour (15 minutes) per day using a computer for leisure. Individuals ages 15 to 19 spend 0.9 hour per day using a computer for leisure. If these times follow an exponential distribution, find the proportion of each group that spends: Less than 14 minutes per day using a computer for leisure. (Round your answers to 4 decimal places.) More than 2 hours. (Round your answers to 4 decimal places.) Between 28 minutes and 84 minutes using a computer for leisure. (Round your answers to 4 decimal places.) Find the 25th percentile. Seventy-five percent spend more than what amount of time? (Round your answers to 2 decimal places.)

Answer 1

a)

Less than 14 minutes per day:

for Individuals age 75 and over P(X<14)=1-e^-14/15 =0.6068

for Individuals ages 15 to 19  P(X<14)=1-e^-14/54 =0.2284

b)More than 2 hours

for Individuals age 75 and over =0.0003

for Individuals ages 15 to 19 =0.1084

c)Between 28 minutes and 84 minutes

for Individuals age 75 and over =0.1509

for Individuals ages 15 to 19 =0.3843

d)

25h percentile:

for Individuals age 75 and over =4.3152 minutes

for Individuals ages 15 to 19 =15.5348 minutes