In: Statistics and Probability
A study conducted by the Metro Housing Agency in a midwestern city revealed the following information concerning the age distribution of renters within the city. (Round your answers to four decimal places.)
Age | Adult Population, % | Group Who Are Renters, % |
---|---|---|
21-44 | 44 | 57 |
45-64 | 35 | 40 |
65 and over | 21 | 63 |
(a) What is the probability that an adult selected at random
from this population is a renter?
(b) If a renter is selected at random, what is the probability that
he or she is in the 21-44 age bracket?
(c) If a renter is selected at random, what is the probability that
he or she is 45 years old or older?
Solution(a)
Total number of adults = 44+35+21+57+40+63 = 260
We need to calculate the probability that an adult selected at
random from this population is a renter which can be calculated
as
P(Renter) = Total number of adults in who are renters / Total
Number of adults = (57+40+63)/257 = 160/260 = 0.6154
So there is a 61.54% probability that an adult selected at random
from this population is a renter.
Solution(b)
Here we need to calculate the probability that he or she is in the
21-44 age bracket if a renter is selected so we will use
conditional probability which can be calculated as
P(21-44 age bracket | Renter)= P(21 - 44 Age bracket and Renter)/
P(Renter) = (Total number of adults in 21-44 age bracket and
Renter/ Total number of adults)/(Total number of renter/Total
number of adults)= (57/260)/((57+40+63)/260) = 57/160 =
0.3563
So there is a 35.63% probability that he or she is in the 21-44 age
bracket If a renter is selected at random.
Solution(c)
Here we need to calculate the probability that he or she is in 45
years old or older age bracket if a renter is selected so we will
use conditional probability which can be calculated as
P(45 old and older age bracket | Renter)= P(45 old and older age
bracket and Renter)/ P(Renter) = (Total number of adults in 45 old
and older age bracket and Renter/ Total number of adults)/(Total
number of renter/Total number of adults)=
((40+63)/260)/((58+42+57)/260) = 103/160 = 0.6437
So there is a 64.37% probability that he or she is in the 45 old or
older age bracket If a renter is selected at random.