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:
v = 25
Step-by-step explanation:
The crucial information you need to know to solve this is to realize that HI and GH are the same length. However, why they are equal is not immediately obvious.
Both sides of the middle line (HF) are symmetrical, since G and I are the same distance away from the line, and they both lie on a line perpendicular to the middle line.
Note: we know they're the same distance away due to the small red marks in the lines, indicating that they're the same length.
The angles at G and I in the triangles are also the same, as the lines from G and I both meet at H. If they were different angles, they would each hit a different point on the middle line.
Thus, we can conclude that GH and HI are the same length.
Since we know the following:
GH = 4v - 75
HI = v
We can set GH and HI equal to each other and solve the equation.
4v - 75 = v
Subtract v from both sides:
3v - 75 = 0
Add 75 to both sides:
3v = 75
Divide both sides by 3:
v = 25
Answer: v = 25
<h3>
Answer: Choice A</h3>
This is because we're adding -6 to each term, i.e. subtracting 6 from each term, to get the next term
- -2+(-6) = -8
- -8+(-6) = -14
- -14+(-6) = -20
- -20+(-6) = -26
and so on. The gap between adjacent terms is the same width. We say that the common difference is d = -6.
21/2 is what you should get if you divide those two
The answer is D.
The formula for the volume of a sphere is
You would divide the diameter in half which would give you your radius (r).
Then you plug in the radius value to find the volume of ONE ball.
You would then multiply by 10 to find the volume of TEN golf balls.
D is the closest answer to the volume of ten golf balls