Mean

\bar{x} = \frac{\Sigma x}{n} = \frac{30}{3} = 10

Mean10.00

Sum30

Value 14

Value 210

Value 316

Pivot5

Set the three values so the mean is exactly 10
Move the pivot until the seesaw balances
Make one value much bigger than the rest and pull the mean above 15
Find three DIFFERENT values (no two the same) whose mean is exactly 8
Balance the seesaw exactly while keeping the smallest value below 3 and the largest above 17