Answer:
see below
Step-by-step explanation:
5^2 means 5*5 not 5*2
5^2 = 5*5 = 25 not 10
Let X be the national sat score. X follows normal distribution with mean μ =1028, standard deviation σ = 92
The 90th percentile score is nothing but the x value for which area below x is 90%.
To find 90th percentile we will find find z score such that probability below z is 0.9
P(Z <z) = 0.9
Using excel function to find z score corresponding to probability 0.9 is
z = NORM.S.INV(0.9) = 1.28
z =1.28
Now convert z score into x value using the formula
x = z *σ + μ
x = 1.28 * 92 + 1028
x = 1145.76
The 90th percentile score value is 1145.76
The probability that randomly selected score exceeds 1200 is
P(X > 1200)
Z score corresponding to x=1200 is
z = 
z = 
z = 1.8695 ~ 1.87
P(Z > 1.87 ) = 1 - P(Z < 1.87)
Using z-score table to find probability z < 1.87
P(Z < 1.87) = 0.9693
P(Z > 1.87) = 1 - 0.9693
P(Z > 1.87) = 0.0307
The probability that a randomly selected score exceeds 1200 is 0.0307
Answer:
$140
Step-by-step explanation:
if 30% of full price = $42 then 100% = 42/0.3 = 140
Answer:
The answer is below
Step-by-step explanation:
The question is not complete, the correct question is:
If B is between A and C, and AB=3x+1, BC=2x-7, and AC=24, then find the value of x and the value of AB
Answer: The line segment addition postulate states that if a point B is placed between a line segment with end points A and C, then the distance between the points can be expressed by the equation:
AB + BC = AC
But AB=3x+1, BC=2x-7, and AC=24, Hence:
3x + 1 + 2x - 7 = 24
3x + 2x + 1 - 7 = 24
5x - 6 = 24
5x = 24 + 6
5x = 30
x = 6
AB = 3x + 1 = 3(6) + 1 = 18 + 1 = 19
BC = 2x - 7 = 2(6) - 7 = 12 - 7 = 5
Answer:
(#14 - supplementary) x = 10.5
(#15 - supplementary) x = 10
Explanation:
For these problems, we must know that a supplementary angle can be viewed as a sum of angles that add to 180 degrees. With this known, we can write our equations to find x.
(#14)
15x - 12 + 5x - 18 = 180
20x - 30 = 180
20x = 210
x = 10.5
(#15)
6x + 13 + 14x - 33 = 180
20x - 20 = 180
20x = 200
x = 10
Hope this helps.
Cheers.
