Answer:
The percentle for Abby's score was the 89.62nd percentile.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation(which is the square root of the variance)
, 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.
Abby's mom score:
93rd percentile in the math SAT exam. In 1982 the mean score was 503 and the variance of the scores was 9604.
93rd percentile. X when Z has a pvalue of 0.93. So X when Z = 1.476.

So




Abby's score
She scored 648.

So



has a pvalue of 0.8962.
The percentle for Abby's score was the 89.62nd percentile.
18 is D and 19 is C you're welcome
Answer:

Step-by-step explanation:
The denominators are the same. You can add the numerators without any extra work.

The denominator factors as (2x-3)(3x+4), so there are no factors that will cancel with the numerator.
Answer:
The nearest 10 is 120
Step-by-step explanation:
<em> 9(x + 2)</em>
- <em>Step-by-step explanation:</em>
<em>Hi ! </em>
<em>6(x+4)+3(x−2) =</em>
<em>= 6x + 24 + 3x - 6</em>
<em>= 6x + 3x + 24 - 6</em>
<em>= 9x + 18</em>
<em>= 9(x + 2)</em>
<em>Good luck !</em>