Answer:the z score is - 1
Step-by-step explanation:
Assuming a normal distribution for the delivery time of sandwiches by Sammy's Sandwich Shop. We would apply the formula for normal distribution which is expressed as
z = (x - u)/s
Where
x = delivery times
u = mean delivery time
s = standard deviation
From the information given,
u = 25 minutes
s = 2 minutes
We want to determine the z-score for the number of sandwiches delivered in less than 23 minutes. It becomes
z = (23 - 25)/2 = - 1
(48a^3 + 32a^2 + 16a) / 4a = ?
48a^3 / 4a = 12a^2
32a^2 / 4a = 8a
16a / 4a = 4
so
(48a^3 + 32a^2 + 16a) / 4a = 12a^2 + 8a + 4
Answer is D. 12a^2 + 8a + 4
From the given information we can write the equation:
-16t^2 +96t + 4 = 112
-16t^2 + 96t + 4 - 112 = 0
-16t^2 + 96t - 108 = 0
simplify, change the signs, divide by -4
4t^2 - 24t + 27 = 0
You can use the qudratic formula but this will factor to
(2t-3)(2t-9) = 0
Two solutions
t = 3/2
t = 1.5 seconds at 112 ft on the way up
and
t = 9/2
t = 4.5 seconds at 112 ft on the way back down
Graphically, (green line is 112 ft)