Let <em>X</em> be the random variable representing the amount (in grams) of nicotine contained in a randomly chosen cigarette.
P(<em>X</em> ≤ 0.37) = P((<em>X</em> - 0.954)/0.292 ≤ (0.37 - 0.954)/0.292) = P(<em>Z</em> ≤ -2)
where <em>Z</em> follows the standard normal distribution with mean 0 and standard deviation 1. (We just transform <em>X</em> to <em>Z</em> using the rule <em>Z</em> = (<em>X</em> - mean(<em>X</em>))/sd(<em>X</em>).)
Given the required precision for this probability, you should consult a calculator or appropriate <em>z</em>-score table. You would find that
P(<em>Z</em> ≤ -2) ≈ 0.0228
You can also estimate this probabilty using the empirical or 68-95-99.7 rule, which says that approximately 95% of any normal distribution lies within 2 standard deviations of the mean. This is to say,
P(-2 ≤ <em>Z</em> ≤ 2) ≈ 0.95
which means
P(<em>Z</em> ≤ -2 or <em>Z</em> ≥ 2) ≈ 1 - 0.95 = 0.05
The normal distribution is symmetric, so this means
P(<em>Z</em> ≤ -2) ≈ 1/2 × 0.05 = 0.025
which is indeed pretty close to what we found earlier.
Answer: The answer is 43.5 because when using the formula you get this result.
Step-by-step explanation: Area of triangle is base x height divided by 2. So do our base 14.5 and our height 6 and multiply them together. 14.5 x 6 = 87 / 2 = 43.5
Answer:
<em>Answer B</em>
Step-by-step explanation:
<u>Fractions on the Number Line</u>
The number line contains an ordered sequence of the numbers, where the smaller numbers are at the left of the greater numbers.
This means -3 is to the left of -2, which is to the left of -1.
Number -2 1/4 lies between -2 and -3.
The only point lying on that interval is B.
Answer B
Answer:
1: 216 selections
2: 120 selections
Step-by-step explanation:
1:
we have 6 different colors and we can choose the same color repeatedly, so for each of the 3 dogs, we have 6 possibilities, so the number of combinations is 6*6*6 = 216 selections.
2:
we have 6 different colors and we can't repeat a color, so the first collar has 6 possibilities, the second has 5 possibilities (one color was already chosen), and the third collar has 4 possibilities (two already chosen), so the number of selections is 6*5*4 = 120.
Answer:
She spent 2 and a half hours doing extra work.
