69-minute overlap 1 time. . Then turn clockwise 1 time 12 hours, which is the coincidence of 12 times, MINUS the first time. Exactly 1 1 time.

So 12 hour of this clock is actually. . 69* 1 1 min. Then 8 hours is 2/3 times of 69* 1 1.

That is 46* 1 1 min. I think it is 506. Divide by 60. . 8.43333333……

That is 80+ 15 * 0.4333 = 86.5.