Chynna has one hour to bake muffins for the PTA bake sale. The muffins take 25 minutes to bake fully. Each pan holds one dozen muffins. The oven holds 4 pans at once. The oven takes 10 minutes to preheat, during which Chynna makes a large amount of batter. Which equation can be used to find p, the number of muffins that Chynna has time to make?