SaiBook.us Decimals

Lesson Example Discussion Quiz: Class Homework

Example

Title: Addition of decimals

Grade: 4-a Lesson: S2-L6

Explanation: The best way to understand decimals is by looking at some examples. Take turns and read each example for easy understanding.

Examples:

Find the sum of \$199.5 + 209.3\$

Step 1a

Given decimals are 199.5 + 209.3

$1a$

Explanation: The given decimals are 199.5 and 209.3, which are like decimals, since each decimal contains one decimal point.

Step 1b

Adding digits, start from the right column and move left. Combine the tenths and decimals in the rightmost column (5+3=8).

$1b$

Explanation: In this step, Start by adding the tenths and decimals on the rightmost column, i.e., 5 + 3 = 8. Record this value in the tenth column of decimal points.

Step 1c

Move to the next column by one’s place in the whole number and add the digits 9 + 9 =18. Write 8 in one’s column, and carry over the 1 in the next column.

$1c$

Explanation: In this step, add the next column in one’s place digits of the whole number which is 9 + 9= 18 place the 8 in one’s column, and carry over the 1 in the next column.

Step 1d

Move to the next column by ten’s place in the whole number and add the digits 9 + 0 =9. Add the carryover number 1 with 9, which is 9 + 1 = 10. Write 0 in ten’s column. And carry over the 1 in the next column.

$1d$

Explanation: In this step, add the next column in ten’s place digits of the whole number which is 9 + 0= 9, and add the carry-over number 1 with 9, while adding 9 and 1 we get 10. place the 0 in ten’s column, and carry the 1 in the next column.

Step 1e

Move to the next column by hundred’s place in the whole number and add the digits 1 + 2 =3. Add the carryover number 1 with 3, which is 3 + 1 =4. Write 4 in the hundred’s column.

Therefore, the sum of 199.5 and 209.3 is 408.8

$1e$

Explanation: Now, let us add the numbers under the hundred’s column. Here, after the carry-over is placed in this column, it is added along with the other addends. This will be, 1 + 2 + 1 (carry-over) = 4.

Hence, the sum of 199.5 + 209.3 = 408.8