answer
46 minutes
set up equation
total = money spent + money left
total = 25 since she started with 25 dollars
money left = 22.24 since this is how much is remaining
money spent = 0.06x where x is the number of minutes, since it cost 6 cents or 0.06 dollars each minute
plug in values and solve
total = money spent + money left
25 = 0.06x + 22.24 subtract 22.24 from both sides
2.76 = 0.06x divide x from both sides
46 = x