Answer:
The probability that a call last between 4.2 and 4.9 minutes is 0.4599
Step-by-step explanation:
Let X be the length in minutes of a random phone call. X is a normal distribution with mean λ=4.2 and standard deviation σ=0.4. We want to know P(4.2 < X < 4.9). In order to make computations, we will use W, the standarization of X, given by the following formula

We will use
, the cummulative distribution function of W. The values of
are well known and the can be found in the attached file

We conclude that the probability that a call last between 4.2 and 4.9 minutes is 0.4599
Parallel:
y
=
2
3
x
−
11
3
y=
3
2
x−
3
11
perpendicular:
y
=
−
3
2
x
+
5
y=−
2
3
x+5
Answer:
the answer is a
Step-by-step explanation:
Answer I think it's 24/1 because if you solve the equation it's 24.
Step-by-step explanation: