Performance comparing
A standardized test was administered to thousands of students with a mean score of 85 and a standard deviation of 8. A random sample of 50 students was given the same test and showed an average score of 83.20. Is there evidence to show that this group has a lower performance than the ones in general at a 0.05 level?
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Miro
For p value we use our normal distribution calcuator:
https://www.hackmath.net/en/calculator/normal-distribution?mean=0&sd=1&above=-1&area=below&below=-1.591&ll=&ul=&outsideLL=&outsideUL=&draw=Calculate
https://www.hackmath.net/en/calculator/normal-distribution?mean=0&sd=1&above=-1&area=below&below=-1.591&ll=&ul=&outsideLL=&outsideUL=&draw=Calculate
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