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.
20 earth pounds on the moon would equate to 3.31 pounds.
I did the work for you but the answer would be 1 second
Answer:
3.14
Step-by-step explanation:
Answer:
x^2 - 8xy + 3y^2 - 2
Step-by-step explanation:
(-8xy + 2x^2 + 3y^2) - unknown = x^2 + 2
- unknown = x^2 + 2 + 8xy - 2x^2 - 3y^2
- unknown = -x^2 + 8xy - 3y^2 + 2
Unknown = x^2 - 8xy + 3y^2 - 2
Check:
(-8xy + 2x^2 + 3y^2) - (x^2 - 8xy + 3y^2 - 2)
= -8xy + 2x^2 + 3y^2 - x^2 + 8xy - 3y^2 + 2
= -8xy + 8xy + 2x^2 - x^2 + 3y^2 - 3y^2 + 2
= x^2 + 2