If you subtract the rest from what you have at the beginning, 783-69=714, which is the flour used for one week, and then divide by 7, which is the flour used for one day. 714/7=12kg。

Steps to solve application problems:

Step 1: Find out the known conditions and problems. To understand the meaning of the question by reading it, the first step is to find out the known conditions and problems. Understand the meaning of the question by reading it, and distinguish the known conditions and questions in the question.

step 2: analyze the quantitative relationship. After understanding the meaning of the question,

Step 3: Analyze the quantitative relationship. After understanding the meaning of the question, it analyzes the known conditions and the problems in the application question, mainly to find out what the relationship between the known conditions is, and to analyze it, mainly to find out what the relationship between the known conditions is.

step 4: calculation in column form. According to the solution steps drawn up above, the formulas are listed for calculation.