Correct Ans:Option A. 0.0100
Solution:We are to find the probability that the class average for 10 selected classes is greater than 90. This involves the utilization of standard normal distribution.
First step will be to convert the given score into z score for given mean, standard deviation and sample size and then use that z score to find the said probability. So converting the value to z score:

So, 90 converted to z score for given data is 2.326. Now using the z-table we are to find the probability of z score to be greater than 2.326. The probability comes out to be 0.01.
Therefore, there is a 0.01 probability of the class average to be greater than 90 for the 10 classes.
We can express this number in the standard form, which is simply 15xyz+10xy+5x. Alternatively, we can factor a 5 or an x out, receiving 5(3xyz+2xy+x) or x(15yz+10y+5). However, the most effective factorization is to factor out 5x, for a result of 5x(3yz+2y+1).
The answer is A) because the parabola is less than 3 (open circle) and the line is greater than and equal to 3 (closed circle)
Answer:
x = -5
Step-by-step explanation:
Get x by itself on the left side. To do that, subtract the 7. Do to both sides. This makes x = -5