The variable z varies jointly with x and y. also, z = -75 when x = 3 and y = -5. what equation describes this variation?

1 answer:

5 0

The equation describing variation will be found as follows:
zαxy
z=kxy
where k is the proportionality constant
k=z/xy
when x=3, y=-5 then z=-75
k=-75/(-5*3)=5
hence the formula will be:
z=5xy

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The probability is 0.0052

Step-by-step explanation:

Let's call A the event that the four cards are aces, B the event that at least three are aces. So, the probability P(A/B) that all four are aces given that at least three are aces is calculated as:

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Because we are going to select 3 aces from the 4 in the poker deck and we are going to select 1 card from the 48 that aren't aces. So the probability in this case is 192/270,725

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$P=\frac{1/270,725}{193/270,725} =\frac{1}{193}=0.0052$