Complete question:
He amount of time that a customer spends waiting at an airport check-in counter is a random variable with mean 8.3 minutes and standard deviation 1.4 minutes. Suppose that a random sample of n equals 47 customers is observed. Find the probability that the average time waiting in line for these customers is
a) less than 8 minutes
b) between 8 and 9 minutes
c) less than 7.5 minutes
Answer:
a) 0.0708
b) 0.9291
c) 0.0000
Step-by-step explanation:
Given:
n = 47
u = 8.3 mins
s.d = 1.4 mins
a) Less than 8 minutes:
P(X' < 8) = P(Z< - 1.47)
Using the normal distribution table:
NORMSDIST(-1.47)
= 0.0708
b) between 8 and 9 minutes:
P(8< X' <9) =![[\frac{8-8.3}{1.4/ \sqrt{47}}< \frac{X'-u}{s.d/ \sqrt{n}} < \frac{9-8.3}{1.4/ \sqrt{47}}]](https://tex.z-dn.net/?f=%20%5B%5Cfrac%7B8-8.3%7D%7B1.4%2F%20%5Csqrt%7B47%7D%7D%3C%20%5Cfrac%7BX%27-u%7D%7Bs.d%2F%20%5Csqrt%7Bn%7D%7D%20%3C%20%5Cfrac%7B9-8.3%7D%7B1.4%2F%20%5Csqrt%7B47%7D%7D%5D)
= P(-1.47 <Z< 6.366)
= P( Z< 6.366) - P(Z< -1.47)
Using normal distribution table,
0.9999 - 0.0708
= 0.9291
c) Less than 7.5 minutes:
P(X'<7.5) = ![P [Z< \frac{7.5-8.3}{1.4/ \sqrt{47}}]](https://tex.z-dn.net/?f=%20P%20%5BZ%3C%20%5Cfrac%7B7.5-8.3%7D%7B1.4%2F%20%5Csqrt%7B47%7D%7D%5D%20)
P(X' < 7.5) = P(Z< -3.92)
NORMSDIST (-3.92)
= 0.0000
Answer:
radius = arc length / central angle in radians
radius = 4 inches / 5*PI / 12
radius = 4 / 1.308996939 radians
radius = 3.0557749074
radius = 3.0557749074 inches
Step-by-step explanation:
Answer:
5-2n
Step-by-step explanation:
Answer:
y = 2^{x}
Step-by-step explanation:
Given the above data for x and y.
From the algebraic expression;
y = 2^{x}
We can deduce that the value of y is equal to two (2) raise to the power of x.
When x = 1, y = 2
y = 2^{x}
y = 2^{1}
y = 2
When x = 2, y = 4
y = 2^{x}
y = 2^{2}
y = 4
When x = 3, y = 8
y = 2^{x}
y = 2^{3}
y = 8
The above calculations can be used to determine the other values of y with respect to x.
Answer:
1) 
2) 
3) 
Step-by-step explanation:
So we have the two functions:
And we want to find (f+g)(x), (f-g)(x), and (f*g)(x).
1)
(f+g)(x) is the same to f(x)+g(x). Substitute:
Combine like terms:
Add:
So:
2)
(f-g)(x) is the same to f(x)-g(x). So:
Distribute:
Combine like terms:
Simplify:
So:
3)
(f*g)(x) is the same to f(x)*g(x). Thus:
Distribute:
Distribute:
Combine like terms:
Simplify:
So:
