Several people have written me personally with good adaptations of the problem I sent a few days ago, some I thought worth sharing:
The original problem: 3) A set of 11 data values has a mean of 8 and a std dev of 2. At least one of the data items is the value 8. If this value is removed, without replacement from the data set, what will be the std dev of the remaining data? Show all work or calculator entry and results.
Option 1: Same given but offer multiple choice responses a) St dev increases; b) decreases, C) is unchanged D) Insufficient info
Option 2) If a value of 12 is removed what is the impact (with same multiple choice answers)
Option 3) given numbers 8, 10, and 12, which could be removed and have the least impact on the STdev