Sam borrowed money from his mom. He wants to know how much time he has to pay her back. The equation to calculate simple interest is given by: l=\Pr tl=Prt
where "l" represents the amount of interest in dollars, "P" represents the principle amount of money loaned in dollars, "r" is the interest rate as a decimal, and "t" is the time in months the money was borrowed. If the amount loaned was $100, the interet rate is 0.05, and the most he wants to pay in interest is $25, how many months does he have to pay her back in? Round to the nearest month if necessary.