Answer:
x is a variable to fill in something that is unknown. its like a question mark
Step-by-step explanation:
The opposite of -1/2 is 1/2. If you put -1/2 in absolute value, then the answer is 1/2.
Look here in a square which is what I imagine that drawing is all the angles are 90 degrees. A rectangle would be knowing two angles is know all of them one way or another so fix your work and you should know the answer
Answer:
(8,-2)
Step-by-step explanation:
When reflecting something across the X axis the y axis coordinate is the one that will change to put the position further up or down. In this case we are moving it down to the same amount below the axis that it is now above it. That means that since it is currently 2 above the X axis it would then be 2 below the X axis making it at -2 so the coordinates would be (8,-2)
I hope this helps and please don't hesitate to ask if there is anything still unclear!
Answer:
2119 students use the computer for more than 40 minutes. This number is higher than the threshold estabilished of 2000, so yes, the computer center should purchase the new computers.
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:

The first step to solve this question is finding the proportion of students which use the computer more than 40 minutes, which is 1 subtracted by the pvalue of Z when X = 40. So



has a pvalue of 0.7881.
1 - 0.7881 = 0.2119
So 21.19% of the students use the computer for longer than 40 minutes.
Out of 10000
0.2119*10000 = 2119
2119 students use the computer for more than 40 minutes. This number is higher than the threshold estabilished of 2000, so yes, the computer center should purchase the new computers.