Answer: 5x ( x - 5y )
Step-by-step explanation:
Answer:
x = 4.3
Step-by-step explanation:

x= 4.3
Answer:
Step-by-step explanation:
23x + xy - y + 3y + 5 - 20x + 6xy = 23x - 20x + xy + 6xy -y + 3y + 5
= 3x + 7xy + 2y + 5
Errors:1) The combined coefficients of the x terms should be 3x, not 43x
2) The coefficients of the y terms have been multiplied.
3) The constant was left off.
Answer:
A score of 150.25 is necessary to reach the 75th percentile.
Step-by-step explanation:
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.
A set of test scores is normally distributed with a mean of 130 and a standard deviation of 30.
This means that 
What score is necessary to reach the 75th percentile?
This is X when Z has a pvalue of 0.75, so X when Z = 0.675.




A score of 150.25 is necessary to reach the 75th percentile.