Option D, For a standard normal distribution, the expression that is always equal to 1 is P(z ≤ -a) + P(-a≤z≤a) + P(Z≥a).
<h3>
What is standard normal distribution?</h3>
A standard normal distribution is a normal distribution with a mean of zero and standard deviation of 1.
For a standard normal distribution, the total area of a curve is always equal to 1.
total area = P(z≤-a)+P(-a≤z≤a)+P(Z≥a) = 1
Thus, for a standard normal distribution, the expression that is always equal to 1 is P(z ≤ -a) + P(-a≤z≤a) + P(Z≥a).
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Answer:
2r, where r is the number of red marbles
Step-by-step explanation:
Since there is twice as many blue marbles as red marbles, it infers blue marbles = 2 × red marbles.
If there are ten black pens, eight blue pens, and twenty pens in total, then there are 2 red pens. This means that the ratio of red to black is 2:10=1:5. Hope this helps!
Least is 8 greatest is 56
<u>Part a) </u>
we know that
An isosceles triangle has two base angles that are congruent
The sum of two base angles plus the vertex angle is equal to 
degrees
so
In this problem
Solve for x
therefore
<u>the answer part a) is</u>
the value of x is 
<u>Part b)</u> What is the measure of each base angle?
we know that
we have that
substitute the value of x in the equation
therefore
<u>the answer part b) is </u>
the measure of each base angle is 
