Digimon had its 20th anniversary.  When it came out John was twice as old as Jim.  If John is 28 now how old is Jim?
When Digimon came out John would have been 28-20=<<28-20=8>>8
So Jim was 8/2=<<8/2=4>>4 years old
That means John is now 4+20=<<4+20=24>>24
#### 24