Answer:
11.44% probability that exactly 12 members of the sample received a pneumococcal vaccination.
Step-by-step explanation:
For each adult, there are only two possible outcomes. Either they received a pneumococcal vaccination, or they did not. The probability of an adult receiving a pneumococcal vaccination is independent of other adults. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
70% of U.S. adults aged 65 and over have ever received a pneumococcal vaccination.
This means that 
20 adults
This means that 
Determine the probability that exactly 12 members of the sample received a pneumococcal vaccination.
This is P(X = 12).


11.44% probability that exactly 12 members of the sample received a pneumococcal vaccination.
Answer:
$73.60
$345
simple interest = amount deposited x time x interest rate
600 + (600 x 0.055 x 5) = $765
600 + (600 x 0.055 x 5) > $2000
$765 $2000
He would not have $2000 in 5 years
Step-by-step explanation:
Total cost of items purchased = $75 + (2 x $8.50) = 92
If there is a 20% discount, he would pay (100 - 20%) 80% of the total cost =
0.8 x $92 = $73.60
commission earned = percentage commission x amount of sales
10% x $3450
= 0.1 x 3450 = 345
Amount he would have in his account = amount deposited + simple interest
simple interest = amount deposited x time x interest rate
600 x 0.055 x 5 = $165
Amount in his account in 5 years = $165 + 600 = $765
He would have less than $2000 in his account. he would have $765