Answer:
4. Mean: 89
5. Median: 90
6. Mode: None.
Explanation:
To find the mean, add all of the numbers, then divide by the total.
There are 7 numbers in this set.
First, add all of the numbers. Then, divide the sum by 7.

The mean of this data set is 89!
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Now, let's find the median.
The median is the "middle number" of the data set.
First, put all of the numbers in order from least to greatest.
85, 95, 88, 93, 94, 78, 90
↓
78, 85, 88, 90, 93, 94, 95,
The number in the middle of the data set is 90!
Therefore, the median is 90.
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Now, let's find the mode.
The mode is the number that appears most frequently.
85, 95, 88, 93, 94, 78, 90
Since each number appears once, then there is no mode.
Let me know if you have any questions.