**Modeling decimal addition :**

For some real-world problems, we may need to add two or more decimals.

Let us see how decimal addition can be modeled through the following example.

Let us see, how to add the decimals 0.24 and 0.15.

Observe the figure given below.

0.24 and 0.15 are shaded in two different colors. Now the sum of 0.24 and 0.15 is 0.39

That is,

3 tenths and 9 hundredths

Adding decimals is similar to adding wholenumbers. First align the numbers by place value. Start adding at the right and regroup when necessary. Bring down the decimal point into your answer.

Based on the point given above, let us see the other methods to add decimals.

**Method 1 :**

Therefore,

0.24 + 0.15 = 0.39

**Method 2 :**

**Not asaaaaaaaaaaaaaaaaa0 . 2 4 aaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaa+ 0 . 1 5 aaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaa-----------aaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaaaa0 . 3 9 aaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaa-----------**

Therefore,

0.24 + 0.15 = 0.39

**Note :**

In both the methods, arrange the decimal numbers according to the place values and add them.

**Problem 1 :**

Add the following decimals

0.75 and 0.5

**Solution :**

**Not asaaaaaaaaaaaaaaaaa0 . 7 5 aaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaa+ 0 . 2 0 aaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaa-----------aaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaaaa0 . 9 5 aaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaa-----------**

In the above addition of decimals, 0.2 is taken as 0.20, as the first decimal number has two digits on the right side of the decimal point.

**Problem 2 :**

Add the following decimals

28.07, 7.6, 0.008

**Solution :**

**Not asaaaaaaaaaaaaa2 8 . 0 7 0 aaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaa+ 7 . 6 0 0aaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaa0 . 0 0 8aaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaa------------aaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaa3 5 . 6 7 8aaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaasaaaaaaa-------------**

**In the above addition of decimals, 7.6 is taken as 7.600 and 28.07 is taken as 28.070. Because the last decimal number has 3 digits on the right side of the decimal point. **

**Problem 3 :**

Add the following decimals

14.2, 16, 0.542

**Solution :**

**Not asaaaaaaaaaaaaaa 1 4 . 2 0 0 aaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaa(+) 1 6 . 0 0 0 aaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaaa0 . 5 4 2 aaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaa---------------aaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaa3 0 . 7 4 2 aaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaa--------------- aaaaaaaaaaaaaaaaaaaaa **

**In the above addition of decimals, 14.2 is taken as 14.200 and 16 is taken as 16.000. Because the last decimal number has 3 digits on the right side of the decimal point.**

**Problem 4 :**

Add the following decimals

10.653, 0.065, 3

**Solution :**

**Not asaaaaaaaaaaaaaa 1 0 . 6 5 3 aaaaaaaaaaaaaaaaaaaaaas aaaaaaaaaaaaaaaaaa(+)0 0 . 0 6 5 aaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaaa3 . 0 0 0 aaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaa---------------aaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaa 1 3 . 7 1 8 aaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaa-----------------aaaaaaaaaaaaaaaaaaaaaa **** **

**In the above addition of decimals, 3 is taken as 3.000.Because the first and second numbers have 3 digits on the right side of the decimal point.**

**Problem 5 :**

Add the following decimals

38.056, 24.6, 39

**Solution :**

**Not asaaaaaaaaaaaaaa 3 8 . 0 5 6aaaaaaaaaaaaaaaaaaaaaas aaaaaaaaaaaaaaaaaa(+) 2 4 . 6 0 0 aaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaa 3 9 . 0 0 0 aaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaa---------------aaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaa 1 0 1 . 6 5 6aaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaa-----------------aaaaaaaaaaaaaaaaaaaaaa **** **

**In the above addition of decimals, 39 is taken as 39.000. Because the first number has 3 digits on the right side of the decimal point.**

After having gone through the stuff given above, we hope that the students would have understood "Modeling decimal addition".

Apart from the stuff given above, if you want to know more about "Modeling decimal addition", please click here

Apart from the stuff given in this section, if you need any other stuff in math, please use our google custom search here.

**Identifying Integers and Their Opposites****Comparing and Ordering Integers****Absolute Value****Greatest Common Factor****Least Common Multiple****Classifying Rational Numbers****Identifying Opposites and Absolute Value of Rational Numbers****Comparing and Ordering Rational Numbers****Applying GCF and LCM to Fraction Operations****Dividing Fractions****Dividing Mixed Numbers****Solving Multistep Problems with Fractions and Mixed Numbers****Dividing Whole Numbers****Adding and Subtracting Decimals****Multiplying Decimals****Dividing Decimals****Applying Operations with Rational Numbers**

HTML Comment Box is loading comments...

**WORD PROBLEMS**

**HCF and LCM word problems**

**Word problems on simple equations **

**Word problems on linear equations **

**Word problems on quadratic equations**

**Area and perimeter word problems**

**Word problems on direct variation and inverse variation **

**Word problems on comparing rates**

**Converting customary units word problems **

**Converting metric units word problems**

**Word problems on simple interest**

**Word problems on compound interest**

**Word problems on types of angles **

**Complementary and supplementary angles word problems**

**Markup and markdown word problems **

**Word problems on mixed fractrions**

**One step equation word problems**

**Linear inequalities word problems**

**Ratio and proportion word problems**

**Word problems on sets and venn diagrams**

**Pythagorean theorem word problems**

**Percent of a number word problems**

**Word problems on constant speed**

**Word problems on average speed **

**Word problems on sum of the angles of a triangle is 180 degree**

**OTHER TOPICS **

**Time, speed and distance shortcuts**

**Ratio and proportion shortcuts**

**Domain and range of rational functions**

**Domain and range of rational functions with holes**

**Graphing rational functions with holes**

**Converting repeating decimals in to fractions**

**Decimal representation of rational numbers**

**Finding square root using long division**

**L.C.M method to solve time and work problems**

**Translating the word problems in to algebraic expressions**

**Remainder when 2 power 256 is divided by 17**

**Remainder when 17 power 23 is divided by 16**

**Sum of all three digit numbers divisible by 6**

**Sum of all three digit numbers divisible by 7**

**Sum of all three digit numbers divisible by 8**

**Sum of all three digit numbers formed using 1, 3, 4**

**Sum of all three four digit numbers formed with non zero digits**