17.
The number relates to the size die it can take. mhp 17 is 17" 21 is 21" 25 is 25".
the difference between 17 and under 17 years old is that under means younger than 17 and 17 is just 17.
89 - 21 = 68
It is 55 minus 21 = 34
21
21 is the answer
14
13
39
17
17...