How many square feet of outdoor carpet will
we need for this hole?
ft²
8 ft
3 ft
12 fat
4 ft

Figure out the difference between the two options. $60 minus $25 is $35, so you can use $35 worth of 10 cent minutes each day to have the same cost.
I worked that out to be 350 minutes per day.  Then I mulitplied it by three to make three days, and got 1050 minutes. Dividing that by 60 gave me the number of hours I'd have to use: 7.5 hours.

So that's 7.5 hours to break even.  If I use more time than that it will be cheaper to use the second option.