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.




Answer:
X < -9
Step-by-step explanation:
5a +18 < -27
5a < -27 -18
5a < - 45
5a/5 < - 45/5
a < - 9
Answred by Gauthmath
Answer: Peter gets £3
Step-by-step explanation:
Let Angad get x: equation will be 2(3x) + 3x + x = 10
X = 1 = Angad
Peter get 3x = 3*1 = 3
Answer:
Can you please take a better picture
Step-by-step explanation: