Answer:
A.0.4477
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean and standard deviation , the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value 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. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
What is the probability that a randomly selected exam will require between 14 and 19 minutes to grade?
This probability is the pvalue of Z when X = 19 subtracted by the pvalue of Z when X = 14. So
X = 19
has a pvalue of 0.7389.
X = 14
has a pvalue of 0.2912
0.7389 - 0.2912 = 0.4477
So the correct answer is:
A.0.4477
Answer:
When 3x/4 - 13 = -9, x² = 256/9.
Step-by-step explanation:
3x/4 - 13 = -9
Multiply the expression by 4.
3x - 52 = -36
Add 52 to both sides.
3x = 16
Divide both sides by 3.
x = 16/3
Knowing x, let's square it.
(16/3)²
Apply the power to fraction rule.
16²/3²
Evaluate the powers.
256/9.
9514 1404 393
Answer:
(x, y) = (3, 0)
Step-by-step explanation:
The solution space is above the line y = -x+2 in the right half-plane where x > 0. One possible solution is (x, y) = (3, 0).
The answer to this question is 17/20.
If you are solving for a: it equals 3
distribute: 5a + 5=2a +14
get rid of extra number on one side: 5a=2a +9 (subtract 5 from both sides)
get rid of the other variable: 3a=9 (subtract 2a from both sides)
divide to isolate a: 3a/3=9/3 (divide by three on both sides)
answer= a=3