1. second option
2. first option
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:
x = 1
Step-by-step explanation:
Given that y varies inversely as x then the equation relating them is
y = 
← k is the constant of variation
To find k use the condition y = 5 when x = 3
k = yx = 5 × 3 = 15, thus
y = 
← equation of variation
When y = 15 then
15 = ( multiply both sides by x )
15x = 15 ( divide both sides by 15 )
x = 1
Answer:
x = 60
Step-by-step explanation:
The question is asking
$14,700 * (1 - 8%)^x = $100
$14,700 * (1 - 0.08)^x = $100
$14,700 * (0.92)^x = $100
(0.92)^x = $100/$14,700
log(0.92^x) = log($100/$14,700)
x * log(0.92) = log(0.0068027)
x = log(0.0068027)/log(0.92)
x = 59.85
Since this question is asking in terms of years, we always round up (in this case to 60), as it won't fully be worth $100 by the beginning of the 59th year.
Answer:
the future value is $5800.38
Step-by-step explanation:
Given that
The invested amount i.e present value is $500
The rate is 5 % per year so quarterly rate is 5% ÷ 4 = 1.25%
The time period is 3 per year so for quartely it is 3 × 4 = 12
We need to find out the future value
So as we know that
Future value = Present value × (1 + rate of interest)^time
= $500 × (1 + 0.0125)^12
= $580.38
hence, the future value is $5800.38
