If x and y vary inversely, and x = 8 when y = 1/4, what is y when x = -4?

1 answer:

3 0

$y \propto \dfrac 1x\\\\\implies y = \dfrac kx \\\\\implies \dfrac 14 = \dfrac k{8}\\\\\implies k=2\\\\\text{When}~ x =-4\\\\y = \dfrac{k}{x} = \dfrac{2}{-4}= -\dfrac 12$

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Homework:Assignment 3 Question 20 Score: 0 of 1 point A vending machine dispenses coffee into -ounce cup. The amount of coffee

xxMikexx [17]

Answer:

19.92

Step-by-step explanation:

To overfill 5% of the time ;

The Zscore (value) to the left of (1 - 0.05) = 0.95 is 1.645

Using this Zscore value with the Zscore formula :

Zscore = (x - μ) / σ

σ = 0.05 ; x = 20 ounce

Substituting into the Zscore formula :

1.645 = (20 - μ) / 0.05

1.645*0.05 = 20 - μ

0.08225 = 20 - μ

μ = 20 - 0.08225

μ = 19.91775

μ = 19.92

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3 years ago

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Dennis_Churaev [7]

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