How many times do the digits of a digital clock add up to 6 in a 12 hour period?

The short answer is "27" and we have to make a number of assumptions because the question as described enough is vague.

So let us assume:

- we are only considering a clock displaying HH:MM where HH is hours and MM is minutes.

- we start the 12 hour period at 00:00 (midnight).

- we must add all 4 digits individually. So 11:11 is 1+1+1+1 not 11+11

- The sum of all 4 digits must equal 6

01:05

01:14

01:23

01:32

01:41

01:50

02:04

02:13

02:22

02:31

02:40

03:03

03:12

03:21

03:30

04:02

04:11

04:20

05:01

05:10

06:00

11:04

11:13

11:22

11:31

11:40

If you start the clock at midday then the options are:

12:03

12:12

12:21

12:30

13:02

13:11

13:20

14:01

14:10

15:00

20:04

20:13

20:22

20:31

20:40

21:03

21:12

21:21

21:30

22:02

22:11

22:20

23:01

23:10