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About Average printable sheet


Can you find sets of positive integers that satisfy the following?

1. Three numbers with mean $3$ and mode $2$

2. Three numbers with mean $7$ and mode $10$

3. Three numbers with mean $8$, median $10$ and range $8$

4. Four numbers with mean $7.5$, mode $6$ and median $7$

5. Four numbers with mean $6$, median $6.5$ and range $11$

6. Five numbers with mean $4$, mode $3$ and range $9$

7. Five numbers with mean $4$, mode $2$ and range $6$ (two possible solutions)

8. Five numbers with mean $7$, mode $7$ and range $10$ (three possible solutions)


Extension

Can you find a set of four numbers with mean $4$, mode $1$, median $2$ and range $10$?

How about a set of five numbers?
Or six numbers?
Or...
Or 100 numbers? 

 


If you enjoyed this problem, you may also be interested in M, M and M.

With thanks to Don Steward, whose ideas formed the basis of this problem.

 

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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