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
Answer:
4x^2 -12x +9 ft^2
Step-by-step explanation:
The area of a square is
A = s^2 where s is the side length
A = (2x-3) ^2
A = (2x-3) (2x-3)
FOIL
first 2x*2x =4x^2
outer 2x (-3) = -6x
inner -3*2x = -6x
last -3*-3 = 9
Add them together
4x^2 -6x-6x +9
Combine like terms
4x^2 -12x +9
The area is 4x^2 -12x +9 ft^2
Answer:
B. -90
Step-by-step explanation:
a1=9; d=-3
a34=9-3(33-1)=-90
Answer:
C) 125°
Step-by-step explanation:
Supplementary angles add to 180 degrees. Complementary angles add to 90
An angle's complement is 35°.
35+x =90
Subtract 35 from each side
35 -35+x = 90-35
x = 55
We want to find the supplement of this angle
55+y = 180
Subtract 55 from each side
55-55+y = 180-55
y= 125
The angle is 55 so its supplement is 125