Answer:
The passing score is 645.2
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:
If the board wants to set the passing score so that only the best 10% of all applicants pass, what is the passing score?
This is the value of X when Z has a pvalue of 1-0.1 = 0.9. So it is X when Z = 1.28.
The passing score is 645.2
1 week = 7 days
10 weeks = 10×7 days
= 70 days
if Ellen reads 1 book in a day
Therefore,
1 day = 1 book
70 days = 70×1
= 70 books.
Thus Ellen reads 70 books in 10 weeks.
Hope helps
Answer:
There are 3 adult tickets and 7 child tickets
Step-by-step explanation:
You are very close.
Let x = the number of adult tickets
Let y = number of child tickets
24.95x+ 15.95y = 186.50
The total number of tickets is 10
x+y =10
Subtract y from each side
x+y-y = 10-y
x =10-y
Substitute this into the first equation
24.95x+ 15.95y = 186.50
24.95(10-y) +15.95y = 186.50
Distribute
249.5 - 24.95y +15.95y =186.5
Combine like terms
249.5 - 9y = 186.50
Subtract 249.5 from each side
249.5-249.5 - 9y = 186.50-249.5
-9y =-63
Divide each side by -9
-9y/-9 = -63/-9
y =7
Now we need to find x
x+y =10
x+7 =10
Subtract 7 from each side
x+7-7 =10-7
x =3
There are 3 adult tickets and 7 child tickets
Y = 1
Using y = mx + c.
Compare to y = 1, y = 0x + 1 ,
We can see that the slope m = 0 and the vertical intercept, c = 1.
For the line perpendicular to y = 1
Condition for perpendicularity m₁m₂ = -1
m₁ = 0, m₂ = ?
0*m₂ = -1
m₂ = -1/0 = Negative Infinite or Infinite
Slope of line perpendicular to y = 1, is = Infinite.
