In English, we can say three fifteen, or a quarter past three to express 3:15. In Chinese, you use 刻 (kè) to mean a quarter. You can even use 三刻 to say three quarters (or 45 minutes)!
三点一刻
(sān diǎn yī kè, 3:15) a quarter past three
九点三刻
(jiǔ diǎn sān kè, 9:45) three quarters past nine
Of course, you can still say 三点十五分 (sān diǎn shíwǔ fēn) for 3:15 and 九点四十五分 (jiǔ diǎn sìshíwǔ fēn) for 5:45.
Minutes to the hour
To say tento or a quarterto in Chinese, use 差十分 (chà shífēn) or 差一刻 (chà yíkè) before or after the hour.