15 is the minuend, 2 is the reduction, and 13 is the difference.

Subtraction formula

1, minuend-subtrahend = difference

2. Difference+Minus = Minus

3, the minuend-difference = reduction

Subtraction correlation characteristic

1, inverse exchange rate: subtraction is inverse exchange. If A and B are any two numbers, then

(A-B) =-(B-A)

2. Anti-association method: subtraction is anti-association. When trying to redefine subtraction, then

a-b-c=a-(b+c)

Extended data addition: operation of combining two numbers into one number/operation of combining two decimals into one decimal/operation of combining two fractions into one fractional subtraction: operation of finding the other addend by knowing two addends and one of them.

Multiplication: A simple operation to find the sum of several identical addends. The meaning of decimal multiplication by integer is the same as that of integer multiplication. Multiplying a number by a pure decimal means finding a few tenths and a few percent of this number ... The meaning of multiplying a fraction by an integer is the same as that of integer multiplication.

Division: the operation of finding another factor by knowing the product of two factors and one of them. It means the same as integer division.