Answers:
The z scores are approximately:
- Care of Magical Creatures: z = 0.333
- Defense Against the Dark Arts: z = 0.583
- Transfiguration: z = -0.263
- Potions: z = -0.533
From those scores, we can say:
- Best grade = Defense Against the Dark Arts
- Worst grade = Potions
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Further Explanation:
We'll need to convert each given score to a corresponding standardized z score.
The formula to use is
z = (x - mu)/sigma
where,
- x = given grade for each class
- mu = mean
- sigma = standard deviation
Let's find the z score for the Care of Magical Creatures class
z = (x - mu)/sigma
z = (3.80 - 3.75)/(0.15)
z = 0.333 approximately
Repeat this process for the Defense Against the Dark Arts score.
z = (x - mu)/sigma
z = (3.60 - 3.25)/(0.60)
z = 0.583 approximately
And for the Transfiguration class as well
z = (x - mu)/sigma
z = (3.10 - 3.20)/(0.38)
z = -0.263 approximately
The negative z score means his grade below the average, whereas earlier the other scores were above the average since he got positive z scores.
Now do the final class (Potions) to get this z score
z = (x - mu)/sigma
z = (2.50 - 2.90)/(0.75)
z = -0.533 approximately
This grade is below average as well.
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To summarize, we have these z scores
- Care of Magical Creatures: z = 0.333
- Defense Against the Dark Arts: z = 0.583
- Transfiguration: z = -0.263
- Potions: z = -0.533
Harry did his best in Defense Against the Dark Arts because the z score of 0.583 (approximate) is the largest of the four z scores. On the other hand, his worst grade is in Potions because -0.533 is the lowest z score.
5 would equal about 11 percent.
9 would equal 1/9 or about 7 - 10 percent.
Answer:
x-5=3x+1 (x=-3)
Step-by-step explanation:
5 less (_-5)
than a number (x)
is equivalent to (=)
1 more than (+1)
than three times the number (3x)
combine them all to get x-5=3x+1
extra:
add 5 to each side x=3x+6
subtract x from each side 0=2x+6
subtract 6 from each side -6=2x
divide each side by 2 -3=x
ANSWER
The equation is

EXPLANATION
Let the equation be

where

is the slope of the line.
We substitute this value to obtain,

Since the line passes through

we can use this point to determine the value of c.
We substitute this point to obtain,



Our equation now becomes

We can write this in standard form as