Answer:
Option B. (4 over 3)*(0.80)^3*0.20
Step-by-step explanation:
Given:
Probability of success p=0.20
Probability of failure q=0.80
To find:
Probability that she wins 1st of 4th ticket.
Solution:
By using binomial distribution formula,
P={nCr *p^k*q^(n-k)}
Total no of combination=nCk
Here n=4 and k=1
So,
total combination =4C1
=4!/(1!*3!)
=4 over 3 =4!/3!
So,
getting the probability that 1st win on fourth ticket with 0.20 % winning chance is
=p^k*q^(n-k)
=0.2^1*0.8(4-1)
=0.2*0.8^3
Hence The probability that she wins 1st that of the fourth ticket is
=(4 over 3)*(0.80)^3*0.20
