SOLUTION: Approximately 10.7% of American high school students drop out of school before graduation. Assume the variable binomial. Choose 12 students entering high school at random. Find the

Algebra ->  Probability-and-statistics -> SOLUTION: Approximately 10.7% of American high school students drop out of school before graduation. Assume the variable binomial. Choose 12 students entering high school at random. Find the      Log On


   

Question 1081721: Approximately 10.7% of American high school students drop out of school before graduation. Assume the variable binomial. Choose 12 students entering high school at random. Find these probabilities.
a) No more than 2 drop out
b) At least 11 graduate
c) All stay in school and graduate
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
All graduate is 0.893^12=0.2572
At least 11, P(11)=12C11*.893^11*0.107=0.3698 + P(12)=0.6270
No more than 2 drop out means that 10, 11, or 12 graduate.
P(10)=12C10*.893^10*0.107^2=0.2437. This is added to the above 0.6270 for 0.8707.