Answer:
Pr(X >42) = Pr( Z > -2.344)
= Pr( Z< 2.344) = 0.9905
Step-by-step explanation:
The scenario presented can be modeled by a binomial model;
The probability of success is, p = 0.65
There are n = 80 independent trials
Let X denote the number of drivers that wear a seat belt, then we are to find the probability that X is greater than 42;
Pr(X > 42)
In this case we can use the normal approximation to the binomial model;
mu = n*p = 80(0.65) = 52
sigma^2 = n*p*(1-p) = 18.2
Pr(X >42) = Pr( Z > -2.344)
= Pr( Z< 2.344) = 0.9905
A plane flew 193 km in 12 minutes at constant speed. what was the speed of the airplane in km per hour? "965 km'
<span>Read the problem entirely.
Get a feel for the whole problem.
List information and the variables you identify.
Attach units of measure to the variables (gallons, miles, inches, etc.)
Define what answer you need, as well as its units of measure.
Work in an organized manner. ...<span>Look for the "key" words (above)</span></span>
10,000 is 8.33% of 120,000.
10,000 / 120,000 = 0.0833 * 100% = 8.33%
Assuming that the whole and percentage is given. find the value of the percentage.
120000 * 8.33% = 9996 ⇒ 10,000
If the percentage is given and its corresponding value. find the whole
10,000 / 8.33% = 120,048 ⇒ 120,000
