Scholastic Aptitude Test (SAT) scores are normally distributed with a mean of 500 points and a standard deviation of 100 points. Suppose you take the SAT and several weeks later you receive a letter telling you that your results on the math portion of the test were in the 90th percentile.

Recalling that SAT scores are always expressed as multiples of 10, how many points did you get on the test?

Question

Scholastic Aptitude Test (SAT) scores are normally distributed with a mean of 500 points and a standard deviation of 100 points. Suppose you take the SAT and several weeks later you receive a letter telling you that your results on the math portion of the test were in the 90th percentile.

Recalling that SAT scores are always expressed as multiples of 10, how many points did you get on the test?

anonymous · Answer

i have noo idea on where to start. or what to do. :l

ankit042 · Answer

using the tables you will find out z value for 0.9 ...I am not sure how to do with calculator
It comes out to be 1.28
then use x = mean +z(std deviation)

amistre64 · Answer

invnorm also gives you the zscore

amistre64 · Answer

2nd, VARS, 3rd option ...

invnorm(.9)

anonymous · Answer

1.28 ?

amistre64 · Answer

yes, unless you have to be more precise

anonymous · Answer

whats is  x = mean +z(std deviation)

amistre64 · Answer

that tells us how many standard deviation you are from the mean

1.28(100)  from 500

amistre64 · Answer

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