20 divided by 4 is 5 so
4$ will be for pay as you go.
5$ will be for regular deal
4+5=9 so the all in one deal is 9$
Answer:
The probability is 0.31
Step-by-step explanation:
In this question, we are tasked with calculating the probability that a random plumber called at Denver will charge an amount greater than $86 given the mean and the standard deviation.
Firstly, we calculate the standard score of $86 using the mean and the standard deviation.
Mathematically;
z-score = (x-mean)/SD
where x = 86, mean = 84 and SD = 4
z-score = (86-84)/4 = 2/4 = 0.5
Hence, we want to calculate P(z ≥ 0.5)
Using standard table
P( (z ≥ 0.5) = 1 - P(z ≤ 0.5) = 1 - ( 0.19146 + 0.5) = 0.30854
To the nearest hundredth = 0.31
This can solved graphically, using algebraic manipulation or differential calculus.
Plotting the equation will generate a parabola. The vertex represents the point where the ball will reach the maximum height.
The vertex can be determined by completing the square
h = -16t2 + 45t + 5
h - 5 = -16(t2 - 45/16t)
h - 5 - 2025/64 = -16(t2 - 45/16t + 2025/1024)
(-1/16)(h - 2345/64) = (t - 45/32)^2
The vertex is
(45/32,2345/64) or (1.41,36.64)
The maximum height is 36.64 ft
Using calculus, taking the first derivative of the equation and equating to 0
dh/dt = 0 = -32t + 45
t = 45/32
Substituting this value to the equation
h = -16(45/32)^2 + 45(45/32) + 5
h = 36.64 ft
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