## Penny Dates

I had a collection of five pennies. The dates on them were:

1996

1993

1987

1990

1994

After I added one more penny to my collection, the mean date changed.

I had a collection of five pennies. The dates on them were:

1996

1993

1987

1990

1994

After I added one more penny to my collection, the mean date changed.

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I noticed that all the pennys were dated from the 1900′s. I also noticed that most of them were from 1990′s. There was only one penny that wasn’t dated from the 1990′s, the 1987. I was wondering if the final penny added had to also not be from the 1990′s in order to change the mean or if it was high like 1999 if that would still drastically change it. I figured that unless the penny was the same as one of the others then the mean would most likely change.

What is the question asking? The mean date will change depending on the date of the sixth penny, but by saying the mean date changed doesn’t provide enough information to answer a question.