i think it's 20 but i'm not that sure
9514 1404 393
Answer:
D.
Step-by-step explanation:
The wording "when x is an appropriate value" is irrelevant to this question. That phrase should be ignored. (You may want to report this to your teacher.)
When you look at the answer choices, you see that all of them are negative except the last one (D). When you look at the problem fraction, you see that it is positive.
The only reasonable choice is D.
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Your calculator can check this for you.
√12/(√3 +3) ≈ 3.4641/(1.7321 +3)
= 3.4641/4.7321 ≈ 0.7321 = -1 +√3
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If you want to "rationalize the denominator", then multiply numerator and denominator by the conjugate of the denominator. The conjugate is formed by switching the sign between terms.

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<em>Additional comment</em>
We "rationalize the denominator" in this way to take advantage of the relation ...
(a -b)(a +b) = a² -b²
Using this gets rid of the irrational root in the denominator, hence "rationalizes" the denominator.
We could also have multiplied by (3 -√3)/(3 -√3). This would have made the denominator positive, instead of negative. However, I chose to use (√3 -3) so you could see that all we did was change the sign from (√3 +3).
50 degrees because 50+50= 100 +80 = 180 and there is 180 degrees in a triangle
Answer:
$301 - $397
Step-by-step explanation:
Using the Empirical rule
1) 68% of data falls within 1 standard deviation from the mean - that means between μ - σ and μ + σ .
2)95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ .
3)99.7% of data falls within 3 standard deviations from the mean - between μ - 3σ and μ + 3σ .
From the above question,
Mean = 349 , standard deviation = 24.
Confidence interval = 95%
Using 2)95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ .
μ – 2σ
= 349 - 2(24)
= 349 - 48
= 301
μ + 2σ
349 + 2(24)
= 349 + 48
= 397
Therefore, according to the standard deviation rule, approximately 95% of the students spent between $301 and $397 on textbooks in a semester.