math
posted by bill .
make up a list of 7 numbers having the following landmarks: mode: 21, median: 24, maximum: 35, range: 20

Start with maximum 35 and range 20, you have the maximum and the minimum.
Knowing that median is the "middle" number, so you have the third.
Mode is the most occuring number, so place 21 at least twice in the right place, and make sure the other numbers do not repeat.
Can you take it from here? 
15, 21, 21, 24, 25, 26, 35