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?
How many kilograms of dog food did Elise buy? ** Elise has bought a total of 15 kg + 10 kg = <<15+10=25>>25kg of dog food.
How many kilograms of dog food did Elise already have? ** This means she already had 40 kg – 25 kg = <<40-25=15>>15kg of dog food.
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