Answer:2
Step-by-step explanation:
Given
Total bags=38
No of bags containing black pen is

No of bags containing blue pen

No of bags containing pencil

no of bags containing both Black pen & blue

no of bags containing both Black pen & Pencil

no of bags containing both Blue pen & Pencil

no of bags containing all

using Venn diagram



and we know


Therefore there are 2 bags which are empty.