Step-by-step explanation:
z-score is:
z = (x − μ) / σ
For the four students:
z = (1990 − 1548) / 319 = 1.39
z = (1280 − 1548) / 319 = -0.84
z = (2240 − 1548) / 319 = 2.17
z = (1450 − 1548) / 319 = -0.31
z-scores are considered significant if they are less than -2 or greater than 2. So the third student's score is unusual.
35/16
If you need the work message me.
289 196 248 379 319 276 198 349
(in order) 196, 198, 248, 276, 289, 319, 349, 379 there are eight numbers.
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196, 198, 248, 276
since the median is between 198 and 248, we must add both numbers together and divide them by two:
(198 + 248) ÷ 2
= 446/2
<h2>
= 223 (first quartile)</h2>
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289, 319, 349, 379
since the median is between 319 and 349, we must add both numbers together and divide them by two:
(319 + 349) ÷ 2
= 668/2
<h2>
= 334 (third quartile)</h2>
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Interquartile range:
<h2>
IQR: 334 - 223 = 111 </h2>
<em>I double-checked my answers btw</em>