Answer:
The probability that 8 mice are required is 0.2428.
Step-by-step explanation:
Given : A scientist inoculates mice, one at a time, with a disease germ until he finds 3 that have contracted the disease. If the probability of contracting the disease is two sevenths.
To find : What is the probability that 8 mice are required? The probability that that 8 mice are required is nothing ?
Solution :
Applying binomial distribution,

Where, p is the probability of success 
q is the probability of failure q=1-p, 
n is total number of trials n=8
r=3
Substitute the values,




Therefore, the probability that 8 mice are required is 0.2428.
The correct answer is B)
I hope this helps.
Have a "AWESOME" day! :)
A mother function is the simplest function of a family of functions.
Answer;
Commutative Property
It is considered commutative when changing the order of the operands does not change the result.
(a brainliest would be appreciated)