Answer:
The mean is 24.205
Step-by-step explanation:
Firstly, we need to get the z-score
From the question, the probability we have is the probability that commuters take more than 22 minutes to commute one-way
So the probability we had was;
P( x > 22)
So we need the z-score corresponding to 63.70% or simply 0.637
We can use the standard normal distribution table to get this
Mathematically, from the standard normal distribution table this is -0.35
z-score = (x- mean)/SD
-0.35 = (22-mean)/6.3
22-mean = -2.205
mean = 22 + 2.205 = 24.205
For zeroes/roots r1,r2, r3
the facors of the polynomial is
(x-r1)(x-r2)(x-r3)
roots
-3,2,5
(x-(-3))(x-2)(x-5)
(x+3)(x-2)(x-5)
the coefient of the x term is -4
so mutliply the whole thing by 2
(2)(x+3)(x-2)(x-5)
expand
f(x)=2x^3-8x^2-22x+60
prime (not composite) as it can only be divided by 1 and itself
Factor out -x from the expression
