Addition of fractions and decimal numbers
43+9.56
1) Convert 9.56 to a fraction: 9.56 = 910056=100956.
2) 43 and 100956 are unlike fractions. The LCM of 4 and 100 is 100.
3) 43 only has to be written as an equal fraction with denominator 100 by multiplying and dividing:
43= 4⋅253⋅25=10075.
4) Find the sum: 43+9.56 = 10075+100956=1001031.
5) 43+9.56=1001031= 1010031=10.31
If a power of 10 is a multiple of the denominator, there is another way to find the sum of a decimal and a fraction. It is as follows:
Convert the fraction to a decimal.
Add the two decimals.
43+9.56:
1) Convert 43 to a decimal:
100 is a multiple of 4. By multiplying and dividing with 25 43 can be converted to an equal fraction:
4 3=4⋅253⋅25=10075=0.75
2) Find the sum: 43+9.56 = 0.75+9.56 = 10.31
Do you have a question?
One way to find the sum of a fraction and a decimal is as follows:
Convert the decimal to a fraction.
If the two fractions are unlike fractions, convert them to like fractions by finding the least common multiple (LCM) of the two denominators. The LCM is taken as a denominator for both fractions.
Convert unlike fractions to like fractions by multiplying and dividing.
Add the like fractions.
Write the sum as a fraction, a mixed fraction and a decimal.
32+4+1.39
You need an adequate knowledge of repeating decimals, of converting a decimal to a fraction and of adding fractions to find the answer.
32 converts to a repeating decimal. Hence, finding the sum is easier if you convert the terminating decimal and the integer to a fraction with a common denominator.
Adhering to the following steps will give you the answer.
Convert the terminating decimal and the integer to a fraction with a common denominator.
Find the least common multiple of all three denominators. The LCM will be the common denominator of the three fractions.
Multiply and divide the fractions if necessary.
Add the fractions.
Simplify.
1) 1.39 = 100139, 4 = 100400
2) The LCM of 3 and 100 is 300.
3) Each of the three fractions has to be converted to an equal fraction with denominator 300:
32=3⋅1002⋅100=300200 , 100400=3⋅100400⋅3=3001200 , 100139=300417
4) Add the fractions.
32+4+1.39 = 300200+3001200+300417=3001817=3001800+30017=630017
5) 30017 cannot be simplified. Hence, the answer is 630017.
Do you have a question?
0.4+72
For this task you need the following basic knowledge: Decimal fractions
For answering this problem, you must have adequate knowledge of repeating decimals, of converting decimals to fractions and of adding fractions.
As 72 converts to a repeating decimal, finding the sum will be easier if the terminating decimal is converted to a fraction.
Adhering to the following steps will give you the answer.
Convert the terminating decimal to a fraction.
Find the least common multiple of the two denominators. The LCM will be the common denominator of the two fractions.
With the LMC as the common denominator for the two fractions, multiply and divide each fraction.
Add the two fractions.
Simplify the sum if possible.
So, Let's get started.
1) 0.4 = 10 4= 52 .
2) 7 2; 52: The LCM of denominators 5 and 7 is 5⋅7=35.
3) Multiply and divide each fraction to convert it to an equal fraction.
52=5⋅72⋅7=3514, 72=7⋅52⋅5=3510 .
4) Add the fractions.
0.4 + 72=3514+3510=3524.
5) 3524 cannot be simplified. Hence the answer is 3524.
Do you have a question?
71+1.7
For this task you need the following basic knowledge: Decimal fractions
You need adequate knowledge of repeating decimals, of converting a (terminating) decimal to a fraction and of adding fractions and mixed numbers.
71 converts to a repeating decimal, 1.7 is a terminating decimal. Hence, finding the sum 71+1.7 is easier if 1.7 is converted to a mixed number. Mixed numbers are usually preferred when adding or subtracting improper fractions.
Adhering to the following steps will give you the answer.
Convert the decimal to a mixed number.
Find the least common multiple of 71 and the denominator of the fraction part of the mixed number. It is the common denominator of 71 and the fraction part of the mixed number.
Multiply and divide 71 and the fraction part of the mixed number.
Add 71 to the mixed number.
Simplify the fraction part if possible.
1) 1.7 = 1107 .
2) The least common multiple of 7 and 10 is 7⋅10 = 70 .
3) Multiplying and dividing:
71=7⋅101⋅10=7010 , 107=10⋅77⋅7=7049 .
4) 71+1.7=7010+17049=17059 .
5) The fraction part of 17059 cannot be simplified.
Hence the answer is 17059 .
Do you have a question?
23+3.44
For this task you need the following basic knowledge: Decimal fractions
This is an easy problem. All you need to know is how to convert an improper fraction to a decimal and how to add decimals.
When adding or subtracting, using mixed numbers is preferred over improper fractions.
The answer can be found after having carried out three steps.
Convert the improper fraction to a mixed number.
If the mixed numbers do not have the same number of decimal places, fill any gaps with a zero. Write the decimal numbers in a vertical list, lining up the decimal points.
Starting with the column with the least place value, add the digits of the column. If the sum is ten or more, do not forget to add the tens digit to the column sum on the left. Do not forget the decimal point in the answer either. It must be lined up with the other decimal points.
So, let's get started.
1) 2 3=22+1=22+21=121=1105= 1.5
2) 1.5 and 3.44 do not have the same number of place values. Fill the gap with a zero:
1.5 = 1.50
Adding the decimals:
1.50+3.444.94
So, 23+3.44 =4.94 .
Do you have a question?
94+1.2+72
For this task you need the following basic knowledge: Decimal fractions
Convert the decimal to a mixed number. Do not simplify the fractional part as the denominator is 10. Multiples of 10 can be easily calculated.
Find the least common multiple of the fractions and the fractional part of the mixed number. The LCM is the common denominator of the the fractions.
Multiply and divide each fraction.
Using the communtative property of addition, first find the sum of the two fractions. Then add this sum to the mixed number.
If possible, simplify the fractional part of the mixed number.
So, let's get started.
1) Convert 1.2 to a mixed number.
1.2 = 1102 .
2) Find the LMC of denominators 9, 10, and 7. Clearly, the highest common factor of these numbers is 1. Hence, the LCM of the numbers is the product of 9, 10, and 7.
9⋅10⋅7 = 630 . This is the common denominator.
3) Multiply and divide.
94 = 9⋅10⋅74⋅10⋅7 =630280 ,
102= 10⋅9⋅72=630126 ,
72=7⋅10⋅92⋅10⋅9 = 630180 .
4) Using the commutative law of addition:
94+72=630280+630180=630460
630460+1.2=630460+1630126=1630586 .
5) The fractional part 630586 of 1630586 can be simplified to 315293 .
So, 94+1.2+72= 1315293 .
Do you have a question?
Knowing how to convert a decimal number to a mixed number as well as how to add mixed numbers and fractions is a prerequisite for finding the sum.
Also, using the commutative property of addition is helpful with finding the sum.
The following steps will give the you the answer.
41+3.2+83+1.7
For this task you need the following basic knowledge: Decimal fractions
This is a fairly easy problem.
Knowing how to add decimals as well as how to convert a fraction to a decimal is a prerequisite for tackling this problem.
41 and 83 convert to terminating decimals. Hence, the above sum will be rewritten in decimal notation and then added as this is quicker than adding fractions.
Adhering to the following steps will take you to the answer.
Convert 41 and 83 to a decimal.
Add the decimals using column addition: Make sure all decimals have the same number of decimal places, fill in any gaps with a zero if necessary; do not forget to line up the decimal points; do not forget to add the decimal point in the answer; if the sum of digits of a column is 10 or more do not forget to carry the tens digit to the column to the left.
So let's get started.
1) Convert to a decimal.
41=4⋅251⋅25=10025=0.25 .
83=8⋅1253⋅125=1000375=0.375 .
2) Add, using column addition.
0.2503.2000.375+11.71505.525
So, 41+3.2+83+1.7 = 5.525 .
Do you have a question?
75+0.3+52
1) Convert the decimal to a fraction.
0.3 = 103 .
2) Find the least common multiple.
The denominators are 7, 10 and 5. As 10 is a multiple of 5, it suffices to find the least common multiple of 7 and 10. As the highest common factor of 7 and 10 is 1, the least common multiple (LCM) of 7 and 10 is 7⋅10= 70 .
3) Multiply and divide.
75= 7⋅105⋅10=7050 .
103=10⋅73⋅7=7021 .
52=5⋅2⋅72⋅2⋅7=7028 .
4) Add the fractions.
75+0.3+52 = 7050+7021+7028=7099 .
5) Convert the improper fraction to a mixed number, simplify the fractional part.
7099=7070+29=7070+7029=17029 .
The fractional part of 17029 cannot the simplified.
Done! The answer is 17029 .
Do you have a question?
As 75 converts to a non-terminating decimal, finding the answer will be easier and quicker if the sum is rewritten in fractional form.
Even though this is a fairly easy exercise, you still must be familiar with converting a (terminating) decimal to a fraction, with adding fractions and, finally, with converting an improper fraction to a mixed number.
Executing the following steps will take you to the answer.
Convert the decimal to a fraction.
Find the least common multiple of the denominators 7, 10, and 5. It is the common denominator of the three fractions.
Multiply and divide each fraction.
Add the fractions.
If possible, convert the sum to a mixed number, simplify its fractional part.
So, let's get going.