1. Open the file to be operated, as shown in the following figure. Column A is the unit price of the commodity, column B is the quantity of the commodity, and column C is the total price of each commodity, as shown in the following figure:

2. Enter "= A2 * B2" and "= A3 * A3" in C2 and C3 cells respectively, as shown in the following figure:

3. Select cells C2 and C3, place the cursor in the lower right corner of C3 until the mouse becomes a black cross, and then drag it down to get the total price of all goods, as shown in the following figure: