Answer:
48 days
Step-by-step explanation:
Swim = every 6 days
Run = every 4 days
Cycles = every 16 days
Find the lowest common multiple of 6, 4 and 16
6 = 6, 12, 18, 24, 30, 36, 42, and 48
4 = 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48
16 = 16, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160
The LCM of 6, 4 and 16 is 48
Therefore,
If she did all 3 activities today, she will do all 3 activities again in the next 48 days
has a unique root, 
, for any 
is a polynomial with roots 
and 