Answer:
m = (-3, 2) x = (-1)
Step-by-step explanation:
Just took this K12 test.
Answer:
a) 40.13% probability that a laptop computer can be assembled at this plant in a period of time of less than 19.5 hours.
b) 34.13% probability that a laptop computer can be assembled at this plant in a period of time between 20 hours and 22 hours.
Step-by-step explanation:
When the distribution is normal, we use 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 question:

a)Less than 19.5 hours?
This is the pvalue of Z when X = 19.5. So



has a pvalue of 0.4013.
40.13% probability that a laptop computer can be assembled at this plant in a period of time of less than 19.5 hours.
b)Between 20 hours and 22 hours?
This is the pvalue of Z when X = 22 subtracted by the pvalue of Z when X = 20. So
X = 22



has a pvalue of 0.8413
X = 20



has a pvalue of 0.5
0.8413 - 0.5 = 0.3413
34.13% probability that a laptop computer can be assembled at this plant in a period of time between 20 hours and 22 hours.
Answer:
About 6 athletes.
Step-by-step explanation:
We are concerned only with the percent of athletes that are above one standard deviation.
Between one standard deviation and two standard deviations, there is 13.6% of the athletes.
From 2 to 3, there is 2.1%. Above 3, there is 0.2%.
The sum of those percentages is 15.9% of 40 = 0.159 · 40 = 6.36 or about 6 athletes.
Hope this helps.
Complementary angels add up to 90°
so x+18°=90°
so x=90-18=72°