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3 years ago

10) A competency test has scores with a mean of 255 and a standard

SAT

1 answer:

melomori [17]3 years ago

8 0

Answer:

The percentage of scores higher than 72 is 99.85%

Explanation:

The empirical rule states that about 68% of observations falls within the first standard deviation (µ ± σ), 95% within the first two standard deviations (µ ± 2σ), and 99.7% within the first three standard deviations (µ ± 3σ)

We can use the relationship below

255-σ(61)=72

61σ=255-72

61σ=183

σ=3

The area is as shaded below

The percentage of scores higher than 72 is 99.7%+0.15%=99.85%

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What it means that [If x is a factor of p(x), what is the value of k?]

kompoz [17]

Answer:

$k = -4$

Explanation:

Given

$P(x) = (3x^2 - 5)(x + k) - 20$

x is a factor

Required

Solve for k

x is a factor means that the polynomial can be divided successfully by x.

In other words, x is a zero of the polynomial.

i.e.

$x = 0$ and $P(x) = 0$

Substitute 0 for x in P(x)

$P(x) = (3x^2 - 5)(x + k) - 20$

$P(x) = (3*0^2 - 5)(0 + k) - 20$

$P(x) = (0- 5)(k) - 20$

$P(x) = (-5)(k) - 20$

$P(x) = -5k - 20$

Substitute 0 for P(x)

$0 = -5k - 20$

Collect Like Terms

$5k = - 20$

Divide both sides by 5

$k = -4$

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3 years ago

The product of two positive integers is 65. Which number could be the sum of the two integers?

Kryger [21]

Answer:

18 is the sum of the two integers.

Explanation:

65 is divisible by 4 numbers: 1, 5, 13, and 65.

Meaning 65 x 1 = 65 and 13 x 5 = 65.

So in this case, add 13 and 5 which equals 18.

18 is the sum of the two integers.

Please like if this helped :)

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2 years ago

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eimsori [14]

Answer:

TRUE

Explanation:

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