Really childish

I went to buy books with my father.

When I arrived at the bookstore, I took Sherlock Holmes for 50.80 yuan and chicken skin for 20 yuan. When it was time to pay the bill, Dad said, "I give the salesperson a hundred yuan. How much should the salesperson look for?" I looked at the price on the back of the book and said, "Let's change the binary."

"Yes, there is progress."

"This is the second grade, it's just a simple death." "You can't say that, I will also help you review the second grade knowledge."

I was speechless... Dad said, "Go, I invite you to eat delicious." "Good," I said.

We came to the cake shop and bought four egg tarts, one for five yuan and four for nine yuan. Dad said, "How much is cheap?"

"I do not want to answer."

"Whatfor"

"Decausenaive (because of childishness)"

"That's good, then don't eat egg tarts."

I can't help but seduce the temptation of food: "It is equal to eleven yuan."

"That's right." Dad said with a smirk, we went home when we ate.

Sixth grade: Zhang Shaolong