To test how long different kinds of french fries, we tested 4 different kinds of fries: McDonald's, Wendy's, Burger King's, and homemade fries. To try and keep the experiment as accurate as possible, we put the fries in dry jars and let them sit for several weeks. After fives days, the McDonald's french fries began to mold as did the Wendy's french fries, which was quite unexpected. Strangely, the mold on the McDonald's french fries disappeared over night, while the Wendy's french fries continued to mold. Even stranger, the homemade fries, which contained no preservatives or additives whatsoever, did not mold.