How do you add decimals with partial sums?
what is a partial sum?
To add decimals using partial sums, follow these steps:
Step 1: Write down the decimal numbers vertically, making sure that the decimal points are in line with each other.
Step 2: Starting from the rightmost digit (the ones place), add up the digits in the same place value column and write the sum below the line.
Step 3: If the sum in any column is greater than 9, carry the tens digit to the next column to the left.
Step 4: Continue adding the digits in the next column, including any carried-over digits, and write the sum below the line.
Step 5: Repeat steps 3 and 4 until you have added all the digits in each column.
Step 6: Align the decimal points in the sum and the numbers being added, and write the final sum.
Let's go through an example:
Example: Add the decimals 3.14, 2.5, and 1.27 using partial sums.
3.14
+ 2.5
+ 1.27
__________
Step 1: Write down the decimals vertically, aligning the decimal points.
3.14
+ 2.50
+ 1.27
__________
Step 2: Start by adding the rightmost column, the ones place:
3.14
+ 2.50
+ 1.27
__________
11
Step 3: There are no carried digits in this column, so we move to the next column:
3.14
+ 2.50
+ 1.27
__________
111
Step 4: Add the digits in the tenths place column:
3.14
+ 2.50
+ 1.27
__________
111
.91
Step 5: Add the digits in the hundredths place column:
3.14
+ 2.50
+ 1.27
__________
111
.91
+.01
__________
Step 6: Align the decimal points and write the final sum:
3.14
+ 2.50
+ 1.27
__________
7.91
So, the sum of 3.14, 2.5, and 1.27 is 7.91.