It’s 12 past 9 (Official clock system).

21:12

It’s 12 past 9.

Correct answer

21:13

It’s 13 past 9.

Error: 1 minute later

21:04

It’s 4 past 9.

Error: read minutes starting from hour markings and adding minutes

14:45

It’s a quarter to 3.

Error: confuse hour and minute hands