Answer:
Skiing costs $30 per hour and Boating costs $51 per hour.
Step-by-step explanation:
Let cost per hour of skiing be x and cost per hour of boating be y. Let's dissect the problem into 2 simultaneous equations.
<em><u>"John paid $222 for four hours of skiing and two hours boating":</u></em>
<em><u>"He paid $213 for two hours skiing and three hours boating":</u></em>
<em>Now, if we solve for x in the 2nd equation and plug it in the 1st equation, we will have the value for y</em>. Work shown below.
Hence, y = 51
<em>Now, substituting this y value into the 1st equation and solving for x will give us the value of x.</em>
Hence, skiing costs $30 per hour and boating costs $51 per hour.
Total number of plants is 74
Bilennial + perennials = 63
63 is 85% or 74
Answer:
ofcourse all perfect squares are divisible by 2
First you need to figure out the slope:
y2-y1/x2-x1=(1+5)/(-5-7)=-1/2
y+5=-1/2(x-7)
y=-1/2x-3/2
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.
