Answer:
0.7698
Step-by-step explanation:
If you call your random variable
, then what you are looking for is

because you want the probability of
being <em>between 87 and 123.</em>
We need a table with of the normal distribution. But we can only find the table with
and
. Because of that, first we need to <em>normalize </em>our random variable:

(you can always normalize your variable following the same formula!)
now we can do something similar to our limits, to get a better expression:


And we transform our problem to a simpler one:
(see Figure 1)
From our table we can see that
(this is represented in figure 2).
Remember that the whole area below the curve is exactly 1. So we can conclude that
(because 0.8849 + 0.1151 = 1). We also know the normal distribution is symmetric, then
.
FINALLY:

Answer:
2.5mph (miles per hour)
Step-by-step explanation:
Simple, 12.5/5 = 2.5 mph (miles per hour)
Answer:
No solution.
Step-by-step explanation:
That image is of the symbol of the empty set. The solution set is empty, which means there is no solution.
The answer is -5 all you have to do is divide -15 by 3
Answer:
59 / 71
Step-by-step explanation:
Given the data :
A B C Total
Male 20 10 13 43
Female 15 2 11 28
Total 35 12 24 71
The probability of randomly selecting a Student that got B ;
Probability = required outcome / Total possible outcomes
P(getting B) = number of students who got B / total number of students
P(getting B) = 12 / 71
Probability of getting B = 12 /71
Probability of not getting B = P(getting B)' = 1 - P(getting B)
Probability that student did not get "B" = 1 - 12/71 = 59 / 71