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:
x = 100°
Step-by-step explanation:
The measure of a chord- chord angle is half the sum of the arcs intercepted by the angle and its vertical angle, that is
x = 
(71 + 129)° = 0.5 × 200° = 100°
Answer:
I assume AC = 49.89 since the number is cut off
Step-by-step explanation:
tangent(degree) = opposite / adjacent
To find AC, you can set up tan(29) = AC / CB
tan(29) = AC / 90 (the picture is cutted off, so I assume....)
= AC
Answer:
Value of x is used to consider unknown value. The letter “x” is commonly used in algebra to indicate an unknown value. It is referred to as a “variable” or, in some cases, a “unknown.” In x + 2 = 7, x is a variable. ... A variable need not be “x,” but might be “y,” "w," or any other letter, name, or symbol.
