9.56? +? 3.5? =? 13.06

5.98? +? 4.59? =? 10.57

9. 12? 4.89? =? 4.23

5.37? 4.5? =? 0.87

6.98? 4.59? =? 2.39

definition

Addition: the operation of combining two numbers into one number.

Subtraction: when two addends and one of them are known, the operation of finding the other addend.

Multiplication: the operation of finding the product of two numbers.

(1) Multiplying a number with an integer is a simple operation, and you can find the sum of several identical addends.

(2) Multiply a number by a decimal to find a few tenths, a few percent and a few thousandths of this number.

(3) A number multiplied by a fraction is a fraction of this number.

Division: the operation of finding another factor by knowing the product of two factors and one of them.