1, number of copies × number of copies = total number of copies/number of copies = total number of copies/number of copies = number of copies.
2. 1 multiple × multiple = multiple1multiple = multiple/multiple = 1 multiple.
3. Speed× time = distance ÷ speed = time ÷ distance ÷ time = speed.
4. Unit price × quantity = total price/unit price = total quantity/quantity = unit price.
5. Work efficiency × working hours = total workload ÷ work efficiency = working hours ÷ total workload ÷ working hours = work efficiency.
6. Appendix+Appendix = sum-one addend = another addend.
7. Minus-Minus = Minus-Minus = Minus+Minus = Minus.