3.9 Plus 9 Addition :

Number 1	Number 2	Answer
3.9	9	12.9

How to calculate 3.9 plus 9 ?

Let's break down the addition of 3.9 and 900 step by step:

   3.9      <-- Start with the rightmost column
+  900
---------

    Add the digits in the rightmost column:
        9 + 0 + 0 = 9
        Write down 9 in the rightmost column, carry over 0 to the next column.

   3.9
+  900
---------
     9


    Add the digits in the rightmost column:
        3 + 9 + 1 = 12
        Write down 2 in the rightmost column, carry over 1 to the next column.

   3.9
+  900
---------
     2.9

    Continue to the left:
        There are no more columns to the left.

The final result is 12.9.

Similar Summation Operations :

Number 1	Number 2	ANSWER:	HOW TO ?
4	18	22	4 plus 18
4.1	23	27.1	4.1 plus 23
4.2	26	30.2	4.2 plus 26
7.8	5	12.8	7.8 plus 5
1.4	0.4	1.8	1.4 plus 0.4
1	6.7	7.7	1 plus 6.7