ANSWER
5 numbers they have in common
EXPLANATION
Set A has all whole numbers to 20:
[tex]A\colon1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20[/tex]
Set B has only odd integer between 8 and 18:
[tex]B\colon9,11,13,15,17[/tex]
We can see that set B is inside set A, because it has whole numbers that are less than 20, so the amount of numbers they have in common is all of set B: 5 numbers.
