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
Answer D
use photomath and sub to pewdiepie
Answer:
13
Step-by-step explanation:
If he reads 119 pgs in 7 days that mean 119/7 = 17 he reads 17 pgs per day
next 340-119 = 221 then 221/17= 13
Answer:
<h2>21/32</h2>
Step-by-step explanation:
-7/8 × -3/4 = 21/32
-7 × -3 = 21
-8 × -4 = 32
21/32
<u><em>IMPORTANT: This number is not negative, because a negative times a negative is a positive.</em></u>
By the way, if you didn't know how to arrive at the fraction here's how.
First, Address input parameters & values.
Input parameters & values: The decimal number = 0.65625. Then, write it as a fraction
0.65625/1
Multiply by 100000 both the numerator & denominator
(0.65625 x 100000)/(1 x 100000) = 65625/100000
65.625% = 65.625/100 or 65625/100000
Find LCM (Least Common Multiple) for 65625 & 100000.
3125 is the LCM for 65625 & 100000
Divide by 3125
65625/100000 = (65625 / 3125) / (100000 / 3125)
= 21/32
I'm always happy to help :)