Number of copies × number of copies = total number of copies/number of copies = total number of copies/number of copies = number of copies.

Speed × time = distance/speed = time/distance/time = speed.

Unit price × quantity = total price/total price = total quantity/quantity = unit price.

Work efficiency × working hours = total workload ÷ work efficiency = working hours.

Total workload ÷ working time = working efficiency

Appendix+Appendix = and-one addend = another addend.

Minus-Minus = Difference Minus-Difference = Minus+Minus = Minus

Factor × factor = product ÷ One factor = another factor.

Dividend/Divider = quotient dividend/quotient = divisor quotient × divisor = dividend

Discount = current price/original price = current price/discount current price = original price × discount

Pay taxes:

Tax rate = tax payable/total income tax payable = total income x tax rate income = tax payable/tax rate

Interest:

Interest rate = interest ÷ principal interest = principal x interest rate x time interest tax = interest x tax rate (5% or 20%)

After-tax interest = interest-interest tax principal and interest = principal+interest (after-tax interest)

Meeting distance = speed × meeting time

Meeting time = meeting distance/speed and

Speed Sum = Meeting Distance/Meeting Time

Downstream velocity = still water velocity+current velocity

Countercurrent velocity = still water velocity-current velocity

Still water velocity = (downstream velocity+countercurrent velocity) ÷2

Water velocity = (downstream velocity-countercurrent velocity) ÷2

(Profit+Loss) ÷ Difference between two distributions = number of shares participating in distribution.

(Big profit-small profit) ÷ Difference between two distributions = number of shares participating in distribution.

(big loss-small loss) ÷ The difference between two distributions = the number of shares participating in the distribution.