SOLUTION: 1.According to company records, 5% of all automobiles brought to Geoff's Garage last year for a state-mandated annual inspection did not pass. Of the next 10 automobiles entering t

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Question 1197433: 1.According to company records, 5% of all automobiles brought to Geoff's Garage last year for a state-mandated annual inspection did not pass. Of the next 10 automobiles entering the inspection station,
a. what is the probability that none will pass inspection?
c. what is the probability that exactly 2 will not pass inspection?
My Work:
a. n=10, x=0, p=0.05
f(x)=10!/10! (10-0)! * 0.05^0*(1-0.05)^10-0
f(x)= 1/1*1(0.95)^10
f(x)=0.598736923838 wrong
c.n=10, p=0.05, x=10-2=8
f(x)=10!/8!(10-8)!*.05^8(1-.05)^(10-8)
=45*2.79310221^-7
=0.00001256895 wrong


Found 2 solutions by math_tutor2020, ikleyn:
Answer by math_tutor2020(3817) About Me  (Show Source):
You can put this solution on YOUR website!

I appreciate you showing your work and thought process.

Part (a)

You have "passed inspection" and "did not pass inspection" mixed up.

The 5% refers to vehicles that did not pass.
So you'll use x = 10, where x is the number of vehicles that didn't pass.









f%2810%29+=+1%2A%280.05%29%5E10%2A%280.95%29%5E%280%29

f%2810%29+=+%280.05%29%5E10

f%2810%29+=+9.765625+%2A+10%5E%28-14%29
Some calculators will display this as 9.765625E-14
The uppercase E refers to "ten to the" where we then specify the exponent after the 10.

To convert this to standard notation, we move the decimal point 14 spots to the left to go from 9.765625 to
0.000  000  000  000  097  656  25
The spacing between the digits is to make the number more readable. Otherwise it would look like this
0.00000000000009765625

Since the number is so incredibly small, it's better to use scientific notation. It'll avoid the tedious pain of having to write out all of those zeros. There are 13 zeros between the decimal point and the digit 9.

===================================================================

Part (b)

This time we use x = 2 so we can determine the probability exactly 2 cars not passing inspection.







f%282%29+=+45%2A%280.05%29%5E2%2A%281-0.05%29%5E%2810-2%29

f%282%29+=+0.07463479852001

The answer is approximately 0.07463479852001

Round that value however your teacher instructs.

Answer by ikleyn(52834) About Me  (Show Source):
You can put this solution on YOUR website!
.


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