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
70000000 the reason that this is the answer to this is because if multiply 10 by 7 you will have 70 and just add 6 zeros
Answer:
48
Step-by-step explanation:
the answer is 48 because according to the results 48% of people prefered given device and 48% of 100 is 48
Answer:
The theater sold a higher ratio of Senior tickets to Adult tickets on the first night.
Step-by-step explanation:
Rate of senior tickets to adult tickets:
Can also be interpreted as the percentage of senior tickets, out of the number of total tickets, which is the number of senior tickets multiplied by 100% and divided by the number of total tickets.
The first night, 19 Senior tickets and 57 Adult tickets were sold.
19 out of 19 + 57 = 76. So
19*100%/76 = 25%
The second night, 20 Senior tickets and 62 Adult tickets were sold.
20 out of 20 + 62 = 82. So
20*100%/82 = 24.39%
25% > 24.39%, so the theater sold a higher ratio of Senior tickets to Adult tickets on the first night.
Answer:
(5, 2 ) and (- 1, 8 )
Step-by-step explanation:
Given the equations
y = - x + 7 → (1)
y = 0.5(x - 3)²
= 0.5(x² - 6x + 9)
y = 0.5x² - 3x + 4.5 → (2)
Substitute y = - x + 7 into (2)
- x + 7 = 0.5x² - 3x + 4.5 ( subtract - x + 7 from both sides )
0 = 0.5x² - 2x - 2.5 ( multiply through by 2 ) , then
x² - 4x - 5 = 0 ← in standard form
(x - 5)(x + 1) = 0 ← in factored form
Equate each factor to zero and solve for x
x - 5 = 0 ⇒ x = 5
x + 1 = 0 ⇒ x = - 1
Substitute these values into (1) for corresponding values of y
x = 5 : y = - 5 + 7 = 2 ⇒ (5, 2 )
x = - 1 : y = -(- 1) + 7 = 1 + 7 = 8 ⇒ (- 1, 8 )