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jeka94
3 years ago
15

In class A, John got 85 for his first test John's class mean was 75 and standard deviation was 5. In class B, Kathy got 80 in he

r first test. Kathy's class mean was 50and standard deviatoin was 10. In a fair comparison of the two studens in two different classes who did better in his or her test. a. John b. Kathyc. same d. none of the above
Mathematics
1 answer:
ivanzaharov [21]3 years ago
6 0

Answer:

b. Kathy

Step-by-step explanation:

We compare each of their score by how far away from the mean when in term of the standard deviation. Using the following formula

\frac{x - \mu}{\sigma}

For John he is (85 - 75)/5 = 2.

For Kathy she is (80 - 50)/10 = 3.

Since Kathy is 3 standard deviation better than her class' average, while John is only 2's. We conclude that Kathy did better.

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I need to know the volume of a rectangular prism 7/4cm,3cm,2cm
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Which of the following ordered pairs represents the solution to the system of equations below?
expeople1 [14]
<span>-3x + 2y = 2  eq (1)

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Mutiply eq (1) by 3 and eq (2) by 2:

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Add th two new equations:

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Now from eq (1)

-3(4) + 2y = 2

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5 0
3 years ago
Please answer quickly<br>expand and simplify: 4(5x-3y) (x-4y) -(3x-4y)(2x+3y)​
Gekata [30.6K]

Answer: 14x^2-93xy+60y^2 Hope that helps!

Step-by-step explanation:

1. Expand by distributing terms

(20x-12y)(x-4y)-(3x-4y)(2x+3y)

2. Use the Foil method:(a+b)(c+d)= ac+ad+bc+bd

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3. Use the Foil method : (a+b)(c+d)= ac+ad+bc+bd

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4. Remove parentheses 20x^2-80xy-12yx+48y^2-6x^2-9xy+ 8yx+12y^2

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5 0
3 years ago
After traveling exactly half of its journey from station A to station B, a train was held up for 10 minutes. In order to arrive
Alex17521 [72]
Let's define variables:
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The original speed of the train before it was held up is:
 
s = 60 Km / h
8 0
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