Question 328654
To roll 100?. I assume you mean 100 inches?.

If the circle revolves 30 dgrees in 1 second, then it takes 12 seconds to make a revolution. The wheel has circumference {{{2*pi*10=20*pi}}} inches.

The circle rolls {{{20*pi}}} inches in 12 seconds.

{{{20*pi/12=100/x}}}

{{{x=60/pi=19.1}}} seconds.