Approximately 15.3% of adult email users were 15–24 years old.
To find the percentage of adult email users who were 15–24 years old, we can calculate the weighted average of the email usage rates across different age groups.
The email usage rates for each age group are given as follows:
68.8% for 15–24 years old
71.6% for 25–44 years old
60.6% for 45–64 years old
40.2% for 65 or older
The proportion of the U.S. adult population in each age group is:
16.9% for 15–24 years old
32.2% for 25–44 years old
32.2% for 45–64 years old
The remaining percentage is for 65 or older.
To find the weighted average, we calculate:
(0.168×0.688)+(0.322×0.716)+(0.322×0.606)+(remaining percentage×0.402)
This computation yields the proportion of adult email users who are 15–24 years old. Rounding the answer to the nearest 1%, we get that approximately 15.3% of adult email users fall into the 15–24 age group.
Complete ques:
Suppose in a certain year, 68.8% of U.S. residents 15–24 years old, 71.6% of those 25–44, 60.6% of those 45–64, and 40.2% of those 65 or older used email. At that time, of the U.S. adult population (15 or older), 16.9% were 15–24 years old, 32.2% were 25–44, 32.2% were 45–64, and the rest were 65 or older. What percentage of adult email users were 15–24 years old? (Round your answer to the nearest 1%.)