2 1/4 = 9/4
(9/4)(8/5) = (9/1)(2/5) = 18/5 = 3 3/5 cups
If you divide 2380 by 4, it will give you 10% of the whole:
1380/4=345
Then you can times 345 by 6 To find the 60%:
345*6=2070
PS Please check my calculations with a calculator as I worked these out in my head.
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.
Let's try plugging in some negative numbers. Let's do x=-1. 5+-1=4. So we know that if we put in a negative number for x, then n will be positive. But what if we do a number greater than -5, because 5+-5=0. So let's try x=-6. So 5+(-6)=-1. Hmm. So here it is. We know that any number under -5 will be positive and any number above -5 will be negative.
Answer:
Maggie is 5 years old
Step-by-step explanation:
3M-4+M=16
add 4 to both sides
4M=20
Divide both sides by 4
20/4 = 5
M/Maggie is 5
