For a standard normally distributed random variable <em>Z</em> (with mean 0 and standard deviation 1), we get a probability of 0.0625 for a <em>z</em>-score of <em>Z</em> ≈ 1.53, since
P(<em>Z</em> ≥ 1.53) ≈ 0.9375
You can transform any normally distributed variable <em>Y</em> to <em>Z</em> using the relation
<em>Z</em> = (<em>Y</em> - <em>µ</em>) / <em>σ</em>
where <em>µ</em> and <em>σ</em> are the mean and standard deviation of <em>Y</em>, respectively.
So if <em>s</em> is the standard deviation of <em>X</em>, then
(250 - 234) / <em>s</em> ≈ 1.53
Solve for <em>s</em> :
16/<em>s</em> ≈ 1.53
<em>s</em> ≈ 10.43
Answer: $8.95 per yard of fabric
Step-by-step explanation:
Define the following:
x = cost of fabric per yard
Make an equation:
⇒ 3x + 1.25 = 28.10
⇒ 3x = 26.85
⇒ x = 8.95
∴ $8.95 per yard of fabric
6a-2(a-1)
6a-2a-2
4a-2
I think it is 4a-2
F(x) = (-3)2 - 5(-3) + q
= -6 + 15 + q
= 9 + q
First calculate the percentage of math.
100-23-30-15-12
=20%
then 150x20% for the math
=30 so there are 30 students chose math.