a medical device company knows that 11% of patients experience injection - site reactions with the current…
a medical device company knows that 11% of patients experience injection - site reactions with the current needle. if 4 people receive injections with this type of needle, what is the probability that none of the 4 people get an injection - site reaction?\n0.0001\n0.3726\n0.4400\n0.6274
Answer
Explanation:
Step1: Find non - reaction probability
The probability of a patient having an injection - site reaction is $p = 0.11$. So the probability of a patient not having an injection - site reaction is $q=1 - p=1 - 0.11 = 0.89$.
Step2: Use independent event formula
Since the events of each of the 4 people not having a reaction are independent, the probability that none of the 4 people get an injection - site reaction is $q^n$, where $n = 4$. So the probability is $0.89^4$. $0.89^4=0.89\times0.89\times0.89\times0.89 = 0.62742241\approx0.6274$
Answer:
0.6274