In mathematics, two-digit multiplication methods are head-to-tail multiplication and head-to-tail addition. Head-to-tail multiplication, in a two-digit multiplication formula, if the ten digits of two multipliers are the same, first add the single digits of the first multiplier to the second multiplier, and then add the mantissas. If the single digits of the two multipliers are the same, the decimal part is multiplied once and the mantissa part is multiplied again.

The function of fast calculation

Mathematical numeration must meet certain conditions before it can be completed, and not all mathematical operations can use quick calculation skills. Only by mastering the basic mathematical operation skills can we use the quick calculation skills when we encounter mathematical operations with certain rules and formulas with special rules for numbers. Learning the skills of two-digit multiplication and fast calculation is of great help to improve the efficiency of mathematical operation and improve the examination results.