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
Answer:
The number is 17
Step-by-step explanation:
Answer:
b-2=n
Step-by-step explanation:
<span>Simplifying
x + -1.4 = 7.82
Reorder the terms:
-1.4 + x = 7.82
Solving
-1.4 + x = 7.82
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '1.4' to each side of the equation.
-1.4 + 1.4 + x = 7.82 + 1.4
Combine like terms: -1.4 + 1.4 = 0.0
0.0 + x = 7.82 + 1.4
x = 7.82 + 1.4
Combine like terms: 7.82 + 1.4 = 9.22
x = 9.22
Simplifying
x = 9.22</span>
P=44.6
P=a+b+√a^2+b^2=11+15+√11^2+15^2≈44.6