Answer:
Weights of at least 340.1 are in the highest 20%.
Step-by-step explanation:
Problems of normally distributed samples are 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.
In this problem, we have that:

a. Highest 20 percent
At least X
100-20 = 80
So X is the 80th percentile, which is X when Z has a pvalue of 0.8. So X when Z = 0.842.




Weights of at least 340.1 are in the highest 20%.
Answer:
The answer you have selected should be correct.
A is the answer to your question
-4x is the slope and -12 is the y-intercept
Answer:
B. 13
Step-by-step explanation:
Solve this by setting up system of equations:
0.25x + 0.10y = 3.95
x + y = 20
x equals the number of quarters and y equals the number of dimes. 0.25 is the value of a quarter and 0.10 is the value of a dime.
1. Multiply one equation to have the same coefficient as the other
0.10 · (x + y = 20) = 0.10x + 0.10y = 2
2. Subtract to find the value of one variable
0.25x + 0.10y = 3.95
<u>- 0.10x + 0.10y = 2</u>
0.15x = 1.95
3. Solve for x by dividing both sides by 0.15
x = 13