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3 years ago

Please help!! I'll give 30 points and brainliest.

Mathematics

1 answer:

Valentin [98]3 years ago

8 0

Step-by-step explanation:

$3 + \frac{9}{4} = \frac{9}{x+4} \\ \\ \therefore \: \frac{3 \times 4 + 9}{4} = \frac{9}{x+4} \\ \\ \therefore \: \frac{12 + 9}{4} = \frac{9}{x+4} \\ \\ \therefore \: \frac{21}{4} = \frac{9}{x+4} \\ \\ \therefore \:21(x + 4) = 36 \\ \\ \therefore \:21x + 84 = 36\\ \\ \therefore \:21x = 36 - 84\\ \\ \therefore \:21x = - 48\\ \\ \therefore \:x = \frac{-48}{21} \\ \\ \therefore \:x = \frac{-16}{7} \\ \\ \huge \red{ \boxed{ \therefore \:x = - 2 \frac{2}{7} }}\\ \\$

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At Hogwarts School of Witchcraft and Wizardry, Professor Snape was concerned about grade inflation, and suggested that the schoo

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Answers:

The z scores are approximately:

Care of Magical Creatures: z = 0.333
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From those scores, we can say:

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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

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Repeat this process for the Defense Against the Dark Arts score.

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And for the Transfiguration class as well

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Now do the final class (Potions) to get this z score

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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

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