A statistics student made the following grades on the first 6 tests: 76, 82, 92, 95, 79, 86. The total number of tests for the semester is 7. What could be her median score for the whole semester?

It’s not possible to answer without knowing the score on the last test.
a.76
b.82
c.92
d.95

Respuesta :

Answer:

It’s not possible to answer without knowing the score on the last test.

Step-by-step explanation:

For this case we have the following data:

76, 82, 92, 95, 79, 86, Final

Where Final represent the score for the last exam

We want to determine if we can calculate the median of this datset without the last score.

We have defined the median as " the midpoint in the frequency distribution of observed values, such that we have an equal probability of falling above or below it."

And when we have a sample size n an odd number the position for the median is calculated as [tex] \frac{n+1}{2}[/tex] if we replace n =7 we got [tex] \frac{7+1}{2}=4[/tex]

The first step on this case is order the dataset given and we got:

76, 79, 82, 86, 92,95

But the problem on this case is that since we don't know the score for the last test we don't know on which position we have for this last score, since for example if the  last score is less than 76 the median would be 82

If the last score is higher than 95 the median would be 86

So as we can see the median depends of the last score position and for this case can't be determined without the information about this last score.

It’s not possible to answer without knowing the score on the last test.