Answer:
P=0.147
Step-by-step explanation:
As we know 80% of the trucks have good brakes. That means that probability the 1 randomly selected truck has good brakes is P(good brakes)=0.8 . So the probability that 1 randomly selected truck has bad brakes Q(bad brakes)=1-0.8-0.2
We have to find the probability, that at least 9 trucks from 16 have good brakes, however fewer than 12 trucks from 16 have good brakes. That actually means the the number of trucks with good brakes has to be 9, 10 or 11 trucks from 16.
We have to find the probability of each event (9, 10 or 11 trucks from 16 will pass the inspection) . To find the required probability 3 mentioned probabilitie have to be summarized.
So P(9/16 )= C16 9 * P(good brakes)^9*Q(bad brakes)^7
P(9/16 )= 16!/9!/7!*0.8^9*0.2^7= 11*13*5*16*0.8^9*0.2^7=approx 0.02
P(10/16)=16!/10!/6!*0.8^10*0.2^6=11*13*7*0.8^10*0.2^6=approx 0.007
P(11/16)=16!/11!/5!*0.8^11*0.2^5=13*21*16*0.8^11*0.2^5=approx 0.12
P(9≤x<12)=P(9/16)+P(10/16)+P(11/16)=0.02+0.007+0.12=0.147
<span>a)
Z*_Upper = (76 - 62.7)/2.5 = 5.32
Z*_Lower = (57 - 62.7)/2.5 = -2.28
The requirement is to get p(-2.28 < Z < 5.32) = p(Z<5.32) - p(Z<-2.28).
Use normal distribution table to get the answer for p and multiply with 100 to get the percentage.
The other questions are now easy for you to answer on your own. Hope it helps.
</span>
Fibonacci saw that every thing could be created with shapes, and that he hoped the world be brighter
The height of the isosceles triangle is 8.49 inches.
<h3>
How to find the height of the triangle?</h3>
Here we have a triangle such that two of the sides measure 9 inches, and the base measures 6 inches.
So this is an isosceles triangle.
We can divide the isosceles triangle into two smaller right triangles, such that the side that measures 9 inches is the hypotenuse, the base is 3 inches, and the height of the isosceles triangle is the other cathetus.
By Pythagorean's theorem, we can write:
(9in)^2 = (3 in)^2 + h^2
Where h is the height that we are trying to find.
Solving that for h we get:
h = √( (9 in)^2 - (3in)^2) = 8.49 inches.
We conclude that the height of the isosceles triangle is 8.49 inches.
If you want to learn more about triangles:
brainly.com/question/2217700
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