The clock face is divided into 60 squares, the minute hand moves one square every minute, and the hour hand moves112 squares every minute. From 6 o'clock, the first time it becomes a right angle, the minute hand goes 15 grid, and the second time it goes 45 grid. In fact, this is catching up with the question:

15 ÷ (1-1/2) =180/11,that is, from 6 o'clock,180.

45 ÷ ( 1- 1/ 12) = 540/ 1 1,

End at 6: 540/ 1 1.

Total 360/ 1 1 min =32 and 1 1 min.