Answer:
Probability that the sample mean comprehensive strength exceeds 4985 psi is 0.99999.
Step-by-step explanation:
We are given that a random sample of n = 9 structural elements is tested for comprehensive strength. We know the true mean comprehensive strength μ = 5500 psi and the standard deviation is σ = 100 psi.
<u><em>Let </em></u>
<u><em> = sample mean comprehensive strength</em></u>
The z-score probability distribution for sample mean is given by;
Z = 
~ N(0,1)
where, 
= population mean comprehensive strength = 5500 psi
= standard deviation = 100 psi
The Z-score measures how many standard deviations the measure is away from the mean. After finding the Z-score, we look at the z-score table and find the p-value (area) associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X.
Now, Probability that the sample mean comprehensive strength exceeds 4985 psi is given by = P( > 4985 psi)
P( > 4985 psi) = P( > 
) = P(Z > -15.45) = P(Z < 15.45)
= <u>0.99999</u>
<em>Since in the z table the highest critical value of x for which a probability area is given is x = 4.40 which is 0.99999, so we assume that our required probability will be equal to 0.99999.</em>
Answer:
1. Her time in minutes is 720/s minutes
2. Given her time to be 20 minutes, her speed is 36 mph
Step-by-step explanation:
Mathematically,
Distance = speed * time
In this question, we want to calculate time;
So time = distance/speed
times = 12 miles/s mph = 12/s hours
Now we want our answer in minutes
Kindly recall that 60 minutes = 1 hour
So 12/s hours will be 12/s * 60 = 720/s minutes
2. Since she drives from home to the office in in 20 minutes, we want to calculate her speed in mph
From the time calculated above i.e 720/s
We can equate 20 = 720/s
20s = 720
s = 720/20
s = 36 mph
Answer:
C. 1000 loss.
Step-by-step explanation:
Let x represent purchase price of each car.
We have been given that a used-car dealer sold one car at a profit of 25 percent of the dealer's purchase price for that car and sold another car at a loss of 20 percent of the dealer's purchase price for that car.
We can represent the car that dealer sold with 25% profit to find purchase price as:
Therefore, the purchase price of 1st car was $16,000.
We can represent the car that dealer sold with 20% loss to find purchase price as:
Therefore, the purchase price of 2nd car was $25,000.
The total purchase price of both cars would be 
The total sale price of both cars 
.
We can see that the sale price of both car is less than purchase price by $1000, so the dealer got a loss of $1000.
Therefore, the dealer's total loss, in dollars, for the two transactions combined was 1000 and option C is the correct choice.
Part A: The discounted monthly fee is $22.49 (original cost of $29.99 multiplied by 75%, the amount the customer would pay since 25% is discounted.) Since you would also pay $44.99 for setup, your equation is $44.99+$22.49m
Part B: Add 1.08 (108%; the customer pays 100% of the cost plus 8% more for tax) to your equation for the sales tax. 1.08(44.99+22.49m)
Part C: Plug in 4 for m (m represents months).
1.08(44.99+22.49•4)
1.08(44.99+89.96)
1.08(134.95)
$145.75
Hope that helps. Let me know if you need more assistance :)
The answer is b hope it helps
