How to do mental math for 23.7+1.95+2.3

First add these because they can make a whole number (they end in 7 and 3 which makes 10=1) 23.7+2.3=25.10=26 Now add 1.95. 26+1.95=27.95

1. Set up the long addition.

2  3 . 7 0
    1 . 9 5
    2 . 3 0


2. Calculate 0 + 5 + 0, which is 5.

2  3 . 7 0
    1 . 9 5
    2 . 3 0

            5

  3. Calculate 7 + 9 + 3, which is 19.
Since 19 is two-digit, we carry the first digit 1 to the next column.
    1
2  3 . 7 0
    1 . 9 5
    2 . 3 0

           9 5

4. Calculate 3 + 1 + 2, which is 6. Now add the carry digit of 1, which is 7.


   1
2  3 . 7 0
    1 . 9 5
    2 . 3 0

     7 . 9 5

5. Calculate 2 + 0 + 0, which is 2.

    1
2  3 . 7 0
    1 . 9 5
    2 . 3 0

   2  7 . 9 5

 6. Therefore, 23.7 + 1.95 + 2.3 = 27.95

27.95

frankly yes, because when you want inverse a function you must inverse it with line x=y

so when you inverse a function Df and Rf will convert together!