Answer: 5/7
Step-by-step explanation: 7/5 is 1.4, which doesn't make sense as an answer here because it's a number greater than one, while we're looking for a number that can be made into a simple fraction, decimal or percent. 5 x 7 = 35, which also doesn't make sense for the same reasons but also because the answer is a division problem and this is multiplication. 7/7 equals one, which doesn't make sense because Melissa hasn't finished 100% of her homework yet. Therefore, the answer is 5/7.