5. Each year, a national achievement test is administered to 3rd graders. The test has a mean score of 100 and a standard deviation of 15. If Jane's z-score is 1.20, what was her score on the test?
118
1.2=(score on the test - 100)/15
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To find Jane's score on the test, we need to use the z-score formula:
z = (x - μ) / σ
Here, z is the z-score, x is the value we want to find (Jane's score), μ is the mean score, and σ is the standard deviation.
Given that Jane's z-score is 1.20, we can plug in the values:
1.20 = (x - 100) / 15
To solve for x (Jane's score), we can rearrange the equation:
1.20 * 15 = x - 100
18 = x - 100
x = 18 + 100
x = 118
Therefore, Jane's score on the test was 118.