Answer:
a) 6.68th percentile
b) 617.5 points
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) A student who scored 400 on the Math SAT was at the ______ th percentile of the score distribution.



has a pvalue of 0.0668
So this student is in the 6.68th percentile.
b) To be at the 75th percentile of the distribution, a student needed a score of about ______ points on the Math SAT.
He needs a score of X when Z has a pvalue of 0.75. So X when Z = 0.675.




X = 7 / sin(45)
x = 7 / sqrt(2)/2
x = 7 sqrt(2)
Step-by-step explanation:
b = 1........... .. ...... .
Triangle Congruence Theorems
Use the triangle congruence theorems below to prove that two triangles are congruent if:
Three sides of one triangle are congruent to three sides of another triangle (SSS: side side side)
Two sides and the angle in between are congruent to the corresponding parts of another triangle (SAS: side angle side)
Two angles and the side in between are congruent to the corresponding parts of another triangle (ASA: angle side angle)
Two angles and the non-included side of one triangle are congruent to the corresponding parts of another triangle (AAS: angle angle side)
The hypotenuse and leg of one right triangle are congruent to the corresponding parts of another right triangle (HL: hypotenuse leg)
Answer:
B: Survey 3 randomly selected students from every homeroom.
Step-by-step explanation:
This would be the best way to survey, because all the others have some sort of variable. The principle doesn't know who buys lunch and who doesn't, so why would he just ask kids who ride in a car as there are kids who ride buses, or only 7th grade students, so the best answer would be something that everyone has, like homeroom.