Since the average height is 60 inches and its deviation is 2 inches, one deviation to the right (or higher) is 62 inches (60 + 2). Two deviations is 64 inches, three deviations is 66 inches, and four deviations is 68 inches.
Since the average weight is 100 pounds and its deviation is 5 inches, we repeat the process from finding heights to get to 115 pounds. That takes three deviations.
The MORE deviations away, the more unusual it is. So the height (4 deviations) is more unusual than the weight (3 deviations).
It would be: 21 * (6.3 * 10⁻⁴)
= 132.3 * 10⁻⁴
= 1.323 * 10⁻²
In short, Your Answer would be: 1.323 * 10⁻²
Hope this helps!
Answer:
-4 ± 2√6
Step-by-step explanation:
Rewritten in standard quadratic form, x^2+8x-2=18 becomes x^2 + 8x - 20 = 0.
Here the quadratic coefficients are a = 1, b = 8 and c = -20 and so the discriminant is b^2 - 4ac, or 8^2 - 4(1)(-20), or 96.
Because the discriminant is positive, we know that this quadratic has two different real roots. These roots are:
-b ± √(b² - 4ac)
x = -------------------------
2a
which in this case comes out to:
-8 ± √96 -8 ± 4√6
x = ------------------ = ------------------- = -4 ± 2√6
2 2
The answer would be about 23% I hope this helps