Question 632705
The 3 clocks each are a piece of the puzzle.
(1)
The wind-up clock gives the true time when 
you returned home which was 5:21 PM.
(2)
The math clock, if you subtract if you
subtract whatever it says from 5:21 PM,
will give you the duration of the power loss.
(3)
The digital clock will tell you when the power
loss started by subtracting it's time from 5:21
----------------------------------------
First, I look at the digital clock and subtract
6 hrs and 3 min from 5:21. That would be 42
min before 12, or 11:18 as the start of the power loss 
----------------------
Then, looking at the math clock, 5:21 minus 3:50
is 1 hr and 31 min. That is the time elapsed during
the power loss.
-----------------------
Also, the power came back on at 11:18 + 1 hr 30 min
or 12:48 PM.
------------------------
To check this, the 3 time periods, before, during, and after
should add up to 5:21 PM - 6:30 AM = 10 hrs 51 min
---------
Before the loss:
11:18 AM - 6:30 AM = 4 hrs 48 min
---------
Duration of the loss:
1 hr 31 min
---------
After the loss:
5:21 PM - 12:48 PM = 4 hrs 33 min
---------
{{{ 4 + 1 + 4 = 9 }}} hr
{{{ 48 + 31 + 33 = 112 }}} min
{{{ 112 = 60 + 52 }}} min
{{{ 1 }}} hr  {{{ 52 }}} min
This adds up to 10 hrs 52 min
I'm 1 min over. There must be a slight
mistake, but I think my method is OK