If a bunny comes out of its hole three times in a minute, in an hour, with 60 minutes, the bunny will come out of the hole 60*3=<<60*3=180>>180 times.
In 10 hours, a bunny will come out of their hole 180*10=<<180*10=1800>>1800 times.
The combined time that 20 bunnies coming out of their holes will have taken in 10 hours is 1800*20=<<1800*20=36000>>36000 times.
#### 36000