Answer: she has 17 CDs now.
Step-by-step explanation:
The total number of CDs that Chen had initially is 17.
She gives 2 to her brother. This means that she would be having
17 - 2 = 15
She buys 4 more. It means that she would be having
15 + 4 = 19
Her brother gives her 1. So the number that she has is
19 + 1 = 20
she gives 3 to her best friend. Therefore, the number of CDs that Chen has now is
20 - 3 = 17
