Answer:
a) The mean is 
b) The standard deviation is 
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
The probability a student selected at random takes at least 55.50 minutes to complete the examination equals 0.6915.
This means that when X = 55.5, Z has a pvalue of 1 - 0.6915 = 0.3085. This means that when 
So




The probability a student selected at random takes no more than 71.52 minutes to complete the examination equals 0.8997.
This means that when X = 71.52, Z has a pvalue of 0.8997. This means that when 
So




Since we also have that 





Question
The mean is 
The standard deviation is 
Answer:
6 29/40
Step-by-step explanation:
1/8 times 5 equals 5/40 and 3/5 times 8 equals 24/40 you add them together to get 29/40 which can not be simplified then add 4 and 2 to get 6 so <u>6 29/40 </u>is your answer.
Answer:
Okay, there are many ways to find if a triangle is congruent.
Let's start with some different terminology.
For the sake of simplicity let us say that S stands for when a side is congruent for both triangles and A stands for when an angle (<) is congruent between both the triangles as well.
So, you need to memorize some rules. If you find that 2 triangles are congruent in the sense of; SSS, SAS, AAS, SAA, and ASA. One thing to remember is that Angle Side Side isn't congruent and is called <em>Donkey Theorem</em>. This theorem only works for right triangles.
One way to know if your triangle isn't congruent is if you can find a part of the triangle that is different.
I know that wasn't the best explanation but I hope it helped anyhow. :)
Answer:
The value of the given expression is 27.1
Step-by-step explanation:
We are given an expression of two variable x and y.
We need to find the value of expression at x = 3 and y = 4
So first put x = 3 and y = 4 into expression and simplify
1/2 x 3 (3) + 3.4 x 4
➡️ 1/2 x 27 + 13.6
➡️ 27/2 + 13.6
➡️ 13.5 + 13.6
Now, add both of the numbers together. ( as an addition problem)
Therefore, when you ad the 2 together, you get the total of 27.1
Answer:
A. $141.75
B. 15% loss (803.25/945)
Step-by-step explanation: