Lizzy: Elise is buying more dog food. She buys a 15kg bag then another 10kg bag, and she now has 40kg of dog food. How many kilograms of dog food did Elise already have?.
Me: Hmmm, let me think. I think this is the detailed solution:
Elise has bought a total of 15 kg + 10 kg = 25kg of dog food. This means she already had 40 kg 25 kg = 15kg of dog food. Final answer: 15.