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4 years ago

2. Kelsea needs a test average of at least 90 to get an "A-" this marking period in math. Her three test grades

Mathematics

1 answer:

Luda [366]4 years ago

6 0

Answer:

Equation: 87 + 91 + 86 + x = 360

Solution: 264 + x = 360

x = 360 - 264

x = 96

Step-by-step explanation:

1. Let's review the information given to us to answer the question correctly:

First three Kelsea's test grades : 87, 91 and 86

2. What score must she get on her fourth test to receive at least an A- ?

Define variable: x that represents the grade needed by Kelsea on her fourth test to receive at least an A-

Equation: 87 + 91 + 86 + x = 360

Solution: 264 + x = 360

x = 360 - 264

x = 96

Now you can understand if the previous work you did is correct

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Answer:

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Step-by-step explanation:

Given

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Required

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For a uniform distribution, we have:

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and

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So, we have:

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$v = x^3$

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$x = v^\frac{1}{3}$

So, the cumulative density is:

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$f(x) = \left \{ {{1\ 9 \le x \le 10} \atop {0\ elsewhere}} \right.$ becomes

$f(x) = \left \{ {{1\ 9 \le x \le v^\frac{1}{3} - 9} \atop {0\ elsewhere}} \right.$

The CDF is:

$F(x) = \int\limits^{v^\frac{1}{3}}_9 1\ dx$

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$F(x) = v^\frac{1}{3} - 9$

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Differentiate F(x) to give:

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So:

$f(v) = \left \{ {{\frac{1}{3}v^{-\frac{2}{3}}\ 9^3 \le v \le 10^3} \atop {0, elsewhere}} \right.$

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