Answer:
{2,4} I know cause I JUST took the same test yesterday :) I guess I didin't help much huh
There are a total 40 cars
and there is x yellow cars
and there are nine times as much white cars (9x white cars) lol
so x+9x=40
simplify 10x=40
divide both sides by ten 10x/10=40/10
x=4
we are looking for the number of WHITE cars sooo we multiply by 9-
9x=36
how is this "hardddd" no offence*
sorry im a mean person
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.
----------------------------
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.
Step-by-step explanation:
Share 20pounds in the ratio 2:3
Total ratio=2+3=5
2/5×20=8
20-8=12
Sharing 20pounds in that ratio gives 8pounds:12pounds
Share 15cm in the ratio 1:3
Total ratio=1+4=4
¼×15=3.75
15-3.75=11.25
Sharing 15cm in that ratio gives 3.75:11.25
Step-by-step explanation:
A. 3x+4/2 = 9.5
3x + 4/2 = 9.5........criss cross
3x+4= 9.5×2
3x = 19-4
3x = 15
x=5 ..........divide both sides by 3
B. 7+ 2x/3= 5.......criss cross
7+2x = 5 × 3
7 + 2x = 15
2x = 15-7
2x = 8......divide both sides by 2
x = 4
