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:
- y = 0.937976x +12.765
- $12,765
- $31,524
- the cost increase each year
Step-by-step explanation:
1. For this sort of question a graphing calculator or spreadsheet are suitable tools. The attached shows the linear regression line to have the equation ...
... y = 0.937976x + 12.765
where x is years since 2000, and y is average tuition cost in thousands.
2. The y-intercept is the year-2000 tuition: $12,765.
3. Evaluating the formula for x=20 gives y ≈ 31.524, so the year-2020 tuition is expected to be $31,524.
4. The slope is the rate of change of tuition with respect to number of years. It is the average increase per year (in thousands). It amounts to about $938 per year.
5. [not a math question]
Answer:
m∠3 = 2x - 10° and m∠6 = 3x + 20
m∠3 = 58° ; m ∠6 = 122°
Step-by-step explanation:
a ║ b
m∠2 = m∠6 If ║ cut by a transversal, then corresponding angles
are ≅ and =
m∠7 = m∠3 If ║ cut by a transversal, then corresponding angles
are ≅ and =
m∠2 = 3x + 20 Given
m∠7 = 2x - 10 Given
m∠6 + m∠3 = 180° If ║ cut by a transversal, then each pair of same-side
interior angles (also called consecutive interior angles
are supplementary (sum = 180°) .
3x + 20 + 2x - 10 = 180°
5x + 10 = 180°
5x = 170°
x = 34°
Answer: m∠3 = 2x - 10° and m∠6 = 3x + 20
m∠3 = 2(34) - 10 ; m∠6 = 3(34) + 20
m∠3 = 58° ; m ∠6 = 122°
A triangle always equals 180 degrees
Answer:
5 units
Step-by-step explanation:
