6 and 1/2= 13/2. 13/2*1/6=13/12 so they spent 1 and 1/12 of an hour on recess
I'm assuming that subtraction sign is mean to be an equals sign. If that is true than the answer is 403.75.
Answer:
1a 3800, 1b 6300 1c 5100
2a 2630, 2b 2600, 2c 3000
3a 4000, 3b 3000, 3c 8000
There are about 8cm in 3.2 inches