Yanna baked twenty butter cookies and forty biscuits in the morning. In the afternoon, she baked ten butter cookies and twenty biscuits. How many more biscuits did she bake than butter cookies? Give me reasons, before answering the question
There were 20 + 10 = 30 butter cookies. And, there were 40 + 20 = 60 biscuits. Therefore, she baked 60 - 30 = 30 more biscuits than butter cookies. So the final answer is 30.