Write down the decimal numbers, one number under the other number and line up the decimal points.

Convert the given decimals to like decimals.

Arrange the addends in such a way that the digits of the same place are in the same column.

Remember to place the decimal point down in the answer in the same place as the numbers above it.

Worked-out problems to find the sum of the decimal numbers:

Read the above explanation step-by-step and try to understand the examples on addition of decimals.

(i) 1.83, 21.105, 236.8 and 0.9

Solution:

We have 1.83 + 21.105 + 236.8 + 0.9

Converting all the addends to like decimals

1.830 + 21.105 + 236.800 + 0.900

(ii) 7.39, 65.007, 213.8 and 91.2

Solution:

We have 7.39 + 65.007 + 213.8 + 91.2

Converting all the addends to like decimals

7.390 + 65.007 + 213.800 + 91.200

2. Terry spent $33 and 65 cents on Monday,$21 on Tuesday and $9 and 7 cents on Wednesday. Find the total money spent by her in three days altogether. Solution: Terry spent on Monday =$43 and 65 cents                                = $33.65 She spent on Tuesday =$21                                                   = $21.00 She spent on Wednesday =$9 and 5 cents                                =  $9.07 Therefore, total amount spent by Terry =$(33.65 + 21.00 + 9.07) = \$63.72

3. First number is 85.99, second number is 107.81 and the third number is 19.207. Find the sum of the three numbers.

Solution:

First number = 85.99

Second number = 107.81

Third number = 19.207

Therefore, sum of three numbers = (85.99 + 107.81 + 19.207) = 213.007

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