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.
The answers will be -5,-1,-1 and 1
Answer:
30cm
Step-by-step explanation:
Area is πr²
So,
πr²=225π
r=√225
r=15cm
Diameter=2r=30
Maths is easy peasy
X+2 is the correct answer
Answer:
2
Step-by-step explanation:
Divide 9/37 and you get repeating decimal of 0.243
Divide 2005 by 3 because the decimal repeats 3 numbers
You will get reminder of 1 from dividing 2005 by 3
Move 1 place from the decimal point and you get 2