In your shoes I would look up "mean," "median" and "mode" to be certain of what they mean. That knowledge (or lack of it) will certainly affect your course grade.
Rearrange the nine given numbers in ascending order: 135, 135, 142, 150, 168, 173, 178, 184, 193.
The mode is the number that shows up most often. That'd be 135. No other number shows up twice.
The median is the middle number of the rearranged seet. That'd be 168.
The mean is the arithmetic average of the 9 numbers. To find that, add up the numbers and divide your sum by 9:
135+135+142+150+168+173+178+184+193
mean: ---------------------------------------------------------------- = 162
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