6th grade Q1

When adding mixed decimals where regrouping is necessary, follow these steps:

Step 1: Line up the decimal points
Write both numbers down with the decimal points lined up. This ensures the digits in each place value are aligned properly.

Step 2: Add each place value from right to left
Start from the right (the smallest place value). Add the digits in each column, moving left. If the sum is 10 or greater in any column, you need to regroup.

Step 3: Write the sum
Once you've added all the digits, write down the final result, making sure the decimal point is in the right place.



Example:

Let’s add these mixed decimals:

Step 1: Line up the decimal points

You can write 4.29 as 4.2900 by adding zeroes at the end to make it easier to align the digits. Adding zeros at the end of a decimal doesn't change it's value.

Step 2: Add each place value starting from the right

The ten-thousandths place: $0+3=3$

The thousandths place: $0+5=5$

The hundredths place: $9+7=16$
16 is greater than 9 so you need to regroup: Write down the 6 in the column and carry over the 1 to the next column on the left. Write the 1 above the next column so you don’t forget it.

The tenths place: $2+4+1=7$
The ones place: $4+2=6$

Step 3: Write the sum

You needed to regroup in the hundredths column, where the sum was greater than 9 (9 + 7 = 16). After regrouping, the rest of the addition was straightforward. Make sure to keep the decimal points aligned throughout the process!