When we finished buying what we needed, we were about to leave. I saw sausages on the shelf, so I asked my mother to buy some sausages, and my mother agreed. But just after a few steps, I saw a package with the same brand and weight on the shelf, which contained 10 pieces at 4.30 yuan each. Do you want to buy a pack or a slice? I hesitated. Suddenly, my mind turned and I understood. Just compare and see which one is cost-effective. So I started to calculate: if I buy 10 pieces in retail, each piece costs 40 cents, which is equal to 4 yuan, and the whole package costs 4.30 yuan, which is 3 cents more, so I decided to buy it in bulk. I told my mother the process of my calculation, and my mother praised me for my love of brains.