Because the number between 6 and 8 is 60 degrees, it is 30 degrees between 7 and 8. If the hour hand goes by B degrees from 7 (counting the story start time now), there will be b/30 = x/60 and b = x/2.
The first relationship: (the first 90 degrees) 180-6x+30+x/2=90, and the solution is x=22 (it is equal, so if you want to keep the score accurate, please calculate it yourself ~ ~), so the beginning is 7: 22.
Because there are two 90 degrees from 7: 00 to 8: 00, not counting the first time, the second time is the one in the story mentioned in the title.
Now the story should be over. It's the same as above, except that the numbers from 6 to 9 are 90 degrees, so the values need to be changed. Shall we set it or set it as above?
The second relationship: (the end point is 90 degrees) 180-6x+45+3x/4=90, and the solution is x=26 (almost equal), so the end point time is 8: 26.
So the total time is 8: 26 minus 7: 22=64 minutes.
You have to draw a picture yourself and compare it with my relationship. I can't go into more detail. I've tried my best ~ ~ ~ Please include it if you don't know.