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Mashutka [201]
3 years ago
15

X is a normally Distributed random variable with a standard deviation of 4.00. Find the mean of X when 64.8% of the area lies to

the left of 8.52.
Mathematics
1 answer:
Cerrena [4.2K]3 years ago
5 0

Answer:

7

Step-by-step explanation:

σ = 4 ; μ =?

8.52 to the left of X

.

P(X < 8.52) = 64.8%

P(X < 8.52) = 0.648

Using the Z relation :

(x - μ) / σ

P(Z < (8.52 - μ) / 4)) = 0.648

The Z value of 0.648 of the lower tail is equal to 0.38 (Z probability calculator)

Z = 8.52 - μ / 4

0.38 = 8.52 - μ / 4

0.38 * 4 = 8.52 - μ

1.52 = 8.52 - μ

μ = 8.52 - 1.52

μ = 7

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Answer:

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Step-by-step explanation:

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klio [65]
You figure out how long it would take a car traveling at 25 mph
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If you're interested, here's how to do it in the other direction:

Let's say a car covers the 360 feet in ' S ' seconds.
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3 years ago
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✧・゚: *✧・゚:*    *:・゚✧*:・゚✧

                  Hello!

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