The clock was exactly on time at 7am at 1pm the clock was 228 seconds late at that rate how slow was the clock half an hour ​

19 seconds.

Step-by-step explanation:

Given that the clock was exactly on time at 7am, and at 1pm the clock was 228 seconds late, to determine, at that rate, how slow was the clock half an hour, the following calculation must be performed:

1 PM = 13:00

13 - 7 = 6

228/6 = 38

38/2 = 19

Thus, every half hour the clock is delayed 19 seconds.