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:
It is always important to go through the given problem first to get a concept of the requiremement. Then all the information's available from the question has to be noted down in such a manner that there would be no need to look at the question while solving.
Total number of students wearing jeans = 10
Total number of students wearing shorts = 9
Total number of students wearing capris = 2
Then the total number of students surveyed by Mrs Lane = (10 + 9 + 2)
= 21
Now percentage of students wearing shorts = (9/21) * 100
= (3/7) * 100
= 300/7
= 42.85 percent
So a total percentage of 42.85% of the students were wearing shorts.
Step-by-step explanation:
-25 - 12x = -(-8x - 6) - 3(5x + 12)
Distributive property.
-25 - 12x = 8x + 6 - 15x - 36
Combine like terms.
-25 - 12x = -7x - 30
Add 12x to both sides.
-25 = 5x - 30
Add 30 to both sides.
5 = 5x
Divide both sides by 5.
x = 1
The x-intersect is 1.
