I hope I'm posting this in the right forum. I'm trying to figure out how many cups of food are in a 5 pound bag, a 10 pound bag and a 15 pound bag of dog food. I'm not good at math and frankly I developed a headache trying to figure it out. By the way, my dog eats once a day, he's 24-25 pounds and is fed 1 cup of food a day. So I'm trying to figure out how long the food lasts from each weight of dog food. In the morning time I give him some doggie biscuits to tide him over until dinner.