SOLUTION: There are 8 cars in a parking lot on a very cold day. Suppose the probability of any of them not starting is 0.13. What is the probability that exactly 2 of the cars will not start

Algebra ->  Probability-and-statistics -> SOLUTION: There are 8 cars in a parking lot on a very cold day. Suppose the probability of any of them not starting is 0.13. What is the probability that exactly 2 of the cars will not start      Log On


   

Question 736990: There are 8 cars in a parking lot on a very cold day. Suppose the probability of any of them not starting is 0.13. What is the probability that exactly 2 of the cars will not start?
Found 2 solutions by mccravyedwin, ikleyn:
Answer by mccravyedwin(417) About Me  (Show Source):
You can put this solution on YOUR website!
On your TI-84 calculator, make sure STATWIZARDS is ON
Press MODE 
Use down arrow key to scroll to NEXT 
Use down arrow to scroll to STATWIZARDS: ON 

Press 2nd vars
Use down arrow key to scroll down to A|binomialpdf(
Press ENTER
Make screen read

   trials:8
   p:0.13
   x value: 2
   Paste

Use down arrow key once to highlight Paste
Press ENTER
See this: 

  binompdf(8,0.3,2)
Press ENTER

Read 0.2051919183   <--ANSWER

Edwin

Answer by ikleyn(53107) About Me  (Show Source):
You can put this solution on YOUR website!
.
There are 8 cars in a parking lot on a very cold day.
Suppose the probability of any of them not starting is 0.13.
What is the probability that exactly 2 of the cars will not start?
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There is no need to explain that this problem is on binomial distribution,
since it is obvious. 


Here the number of trials is 8; the number of successful trials is 2;
the probability of the individual success is p = 0.13.


Use the standard formula on Binomial distribution

    P(n=8, k=2, p=0.13) = C%5B8%5D%5E2%2A0.13%5E2%2A%281-0.13%29%5E%288-2%29 = 28%2A0.13%5E2%2A0.87%5E6 = 0.2052  (rounded).   ANSWER

Solved.