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3 years ago

Solve by transforming into a perfect square trinomial x squared-14x=15

1 answer:

8 0

X^2 - 14 x = 15

(x - 7)^2 - 49 = 15

(x-7)^2 = 64

x - 7 = - or + 8

x = 15 or -1

Just take half o the coefficient of x and subtract it squared as above.

In general

x^2 + ax = b

(x + a/2)^2 - a^2/4 = b

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Consider a population with 3 observations: 6, 10 and 12. You use simple random sampling without replacement to select a sample o

lozanna [386]

Answer:

$\dfrac{2}{3}$

Step-by-step explanation:

Given that:

The number of observations is:

6, 10, 12

If we are to use a simple random sampling without replacement, then we will have:

(6,10) (6,12) (10,12)

Here;

the sample size n = 2

The population size N = 3

For (6,10) ; The sample mean = $\dfrac{6+10}{2}$

= $\dfrac{16}{2}$

= 8

For (6,12) ; The sample mean = $\dfrac{6+12}{2}$

= $\dfrac{18}{2}$

= 9

For (10, 12) ; The sample mean = $\dfrac{10+12}{2}$

= $\dfrac{22}{2}$

= 11

The probability distribution of sample mean(x) is:

X 8 9 11

P(X=x) $\dfrac{1}{3}$ $\dfrac{1}{3}$ $\dfrac{1}{3}$

Thus, the probability that the sample mean is larger than 8 is:

P(X> 8) = P(X = 9) + P(X + 11)

P(X> 8) = $\dfrac{1}{3}+\dfrac{1}{3}$

P(X > 8) = $\dfrac{1+1}{3}$

P(X> 8) = $\dfrac{2}{3}$

5 0

3 years ago

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Reptile [31]

Simplified the answer is 35/12+3v/2

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4 years ago

Find the missing side length in the image below

AfilCa [17]

Answer:

3/6=?/10

Step-by-step explanation:

multiply by together. ?=5

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3 years ago

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Answer:

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Step-by-step explanation:

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3 years ago