Examples with solutions for Addition of Fractions: One of the denominators is the common denominator

Exercise #1

Solve the following equation:

12+38= \frac{1}{2}+\frac{3}{8}=

Video Solution

Step-by-Step Solution

Let's first identify the lowest common denominator between 2 and 8.

In order to determine the lowest common denominator, we need to first find a number that is divisible by both 2 and 8.

In this case, the common denominator is 8.

We'll then proceed to multiply each fraction by the appropriate number in order to reach the denominator 8.

We'll multiply the first fraction by 4

We'll multiply the second fraction by 1

1×42×4+3×18×1=48+38 \frac{1\times4}{2\times4}+\frac{3\times1}{8\times1}=\frac{4}{8}+\frac{3}{8}

Finally we'll combine and obtain the following:

4+38=78 \frac{4+3}{8}=\frac{7}{8}

Answer

78 \frac{7}{8}

Exercise #2

Solve the following equation:

24+12= \frac{2}{4}+\frac{1}{2}=

Video Solution

Step-by-Step Solution

Let's first identify the lowest common denominator between 4 and 2.

In order to identify the lowest common denominator, we need to find a number that is divisible by both 4 and 2.

In this case, the common denominator is 4

We will then proceed to multiply each fraction by the appropriate number in order to reach the denominator 4

We'll multiply the first fraction by 1

We'll multiply the second fraction by 2

2×14×1+1×22×2=24+24 \frac{2\times1}{4\times1}+\frac{1\times2}{2\times2}=\frac{2}{4}+\frac{2}{4}

Finally we will combine and obtain the following:

2+24=44=1 \frac{2+2}{4}=\frac{4}{4}=1

Answer

1 1

Exercise #3

Solve the following equation:

23+16= \frac{2}{3}+\frac{1}{6}=

Video Solution

Step-by-Step Solution

Let's begin by identifying the lowest common denominator between 3 and 6.

In order to determine the lowest common denominator, we need to find a number that is divisible by both 3 and 6.

In this case, the common denominator is 6.

Let's proceed to multiply each fraction by the appropriate number in order to reach the denominator 6.

We'll multiply the first fraction by 2

We'll multiply the second fraction by 1

2×23×2+1×16×1=46+16 \frac{2\times2}{3\times2}+\frac{1\times1}{6\times1}=\frac{4}{6}+\frac{1}{6}

Finally we'll combine and obtain the following result:

4+16=56 \frac{4+1}{6}=\frac{5}{6}

Answer

56 \frac{5}{6}

Exercise #4

Solve the following equation:

24+18= \frac{2}{4}+\frac{1}{8}=

Video Solution

Step-by-Step Solution

We must first identify the lowest common denominator between 4 and 8

In order to determine the lowest common denominator, we need to find a number that is divisible by both 4 and 8.

In this case, the common denominator is 8.

We will proceed to multiply each fraction by the appropriate number to reach the denominator 8.

We'll multiply the first fraction by 2

We'll multiply the second fraction by 1

2×24×2+1×18×1=48+18 \frac{2\times2}{4\times2}+\frac{1\times1}{8\times1}=\frac{4}{8}+\frac{1}{8}

Finally we'll combine and obtain the following:

4+18=58 \frac{4+1}{8}=\frac{5}{8}

Answer

58 \frac{5}{8}

Exercise #5

Solve the following equation:

15+610= \frac{1}{5}+\frac{6}{10}=

Video Solution

Step-by-Step Solution

We must first identify the lowest common denominator between 5 and 10.

In order to determine the lowest common denominator, we need to find a number that is divisible by both 5 and 10.

In this case, the common denominator is 10.

We will proceed to multiply each fraction by the appropriate number to reach the denominator 10.

We'll multiply the first fraction by 2

We'll multiply the second fraction by 1

1×25×2+6×110×1=210+610 \frac{1\times2}{5\times2}+\frac{6\times1}{10\times1}=\frac{2}{10}+\frac{6}{10}

Finally we'll combine and obtain the following:

2+610=810 \frac{2+6}{10}=\frac{8}{10}

Answer

810 \frac{8}{10}

Exercise #6

Solve the following equation:

13+36= \frac{1}{3}+\frac{3}{6}=

Video Solution

Step-by-Step Solution

We must first identify the lowest common denominator between 3 and 6.

In order to determine the lowest common denominator, we need to find a number that is divisible by both 3 and 6.

In this case, the common denominator is 6.

We'll then proceed to multiply each fraction by the appropriate number to reach the denominator 6.

We'll multiply the first fraction by 2

We'll multiply the second fraction by 1

1×23×2+3×16×1=26+36 \frac{1\times2}{3\times2}+\frac{3\times1}{6\times1}=\frac{2}{6}+\frac{3}{6}

Finally we'll combine and obtain the following:

2+36=56 \frac{2+3}{6}=\frac{5}{6}

Answer

56 \frac{5}{6}

Exercise #7

Solve the following equation:

14+612= \frac{1}{4}+\frac{6}{12}=

Video Solution

Step-by-Step Solution

We must first identify the lowest common denominator between 4 and 12.

In order to determine the lowest common denominator, we need to find a number that is divisible by both 4 and 12.

In this case, the common denominator is 12.

We will then proceed to multiply each fraction by the appropriate number to reach the denominator 12.

We'll multiply the first fraction by 3

We'll multiply the second fraction by 1

1×34×3+6×112×1=312+612 \frac{1\times3}{4\times3}+\frac{6\times1}{12\times1}=\frac{3}{12}+\frac{6}{12}

Finally we'll combine and obtain the following:

3+612=912 \frac{3+6}{12}=\frac{9}{12}

Answer

912 \frac{9}{12}

Exercise #8

Solve the following equation:

13+29= \frac{1}{3}+\frac{2}{9}=

Video Solution

Step-by-Step Solution

We must first identify the lowest common denominator between 3 and 9.

In order to determine the lowest common denominator, we need to find a number that is divisible by both 3 and 9.

In this case, the common denominator is 9.

We will then proceed to multiply each fraction by the appropriate number to reach the denominator 9.

We'll multiply the first fraction by 3

We'll multiply the second fraction by 1

1×33×3+2×19×1=29+29 \frac{1\times3}{3\times3}+\frac{2\times1}{9\times1}=\frac{2}{9}+\frac{2}{9}

Finally we'll combine and obtain the following:

2+39=59 \frac{2+3}{9}=\frac{5}{9}

Answer

59 \frac{5}{9}

Exercise #9

Solve the following equation:

13+49= \frac{1}{3}+\frac{4}{9}=

Video Solution

Step-by-Step Solution

We must first identify the lowest common denominator between 3 and 9.

In order to determine the lowest common denominator, we need to find a number that is divisible by both 3 and 9.

In this case, the common denominator is 9.

We will then proceed to multiply each fraction by the appropriate number to reach the denominator 9.

We'll multiply the first fraction by 3

We'll multiply the second fraction by 1

1×33×3+4×19×1=39+49 \frac{1\times3}{3\times3}+\frac{4\times1}{9\times1}=\frac{3}{9}+\frac{4}{9}

Finally we'll combine and obtain the following:

3+49=79 \frac{3+4}{9}=\frac{7}{9}

Answer

79 \frac{7}{9}

Exercise #10

12+24= \frac{1}{2}+\frac{2}{4}=

Video Solution

Step-by-Step Solution

To solve the problem 12+24 \frac{1}{2} + \frac{2}{4} , we'll follow these steps:

  • Step 1: Convert 12 \frac{1}{2} to have a denominator of 4. Multiply the numerator and the denominator by 2 to get 24 \frac{2}{4} .
  • Step 2: With both fractions now having a common denominator, add them: 24+24 \frac{2}{4} + \frac{2}{4} .
  • Step 3: Combine the numerators and place the sum over the common denominator: 2+24=44 \frac{2+2}{4} = \frac{4}{4} .
  • Step 4: Simplify the fraction 44 \frac{4}{4} to 1 1 .

Therefore, the solution to the problem is 1 1 .

Answer

1 1

Exercise #11

35+610= \frac{3}{5}+\frac{6}{10}=

Video Solution

Step-by-Step Solution

To solve this problem, we need to add the fractions 35\frac{3}{5} and 610\frac{6}{10}. Since 610\frac{6}{10} is already expressed with the denominator of 10, we will convert 35\frac{3}{5} to have the same denominator.

Step 1: Convert 35\frac{3}{5} into a fraction with a denominator of 10. To do this, multiply both the numerator and the denominator by 2:

35=3×25×2=610\frac{3}{5} = \frac{3 \times 2}{5 \times 2} = \frac{6}{10}

Step 2: Add the fractions 610\frac{6}{10} and 610\frac{6}{10}:

610+610=6+610=1210\frac{6}{10} + \frac{6}{10} = \frac{6 + 6}{10} = \frac{12}{10}

Step 3: Simplify 1210\frac{12}{10}. Both numerator and denominator can be divided by 2:

1210=12÷210÷2=65\frac{12}{10} = \frac{12 \div 2}{10 \div 2} = \frac{6}{5}

Thus, the sum 35+610\frac{3}{5} + \frac{6}{10} simplifies to 65\frac{6}{5}.

Therefore, the correct answer is 65\frac{6}{5} which corresponds to choice 3.

Answer

65 \frac{6}{5}

Exercise #12

12+38= \frac{1}{2}+\frac{3}{8}=

Video Solution

Step-by-Step Solution

To solve this problem, we need to add the fractions 12 \frac{1}{2} and 38 \frac{3}{8} .

  • Step 1: Convert 12 \frac{1}{2} to a fraction with a denominator of 8. We do this by determining the equivalent fraction 12=48 \frac{1}{2} = \frac{4}{8} . We achieve this by multiplying the numerator and denominator by 4.
  • Step 2: Now, add the fractions 48 \frac{4}{8} and 38 \frac{3}{8} : 48+38=4+38=78 \frac{4}{8} + \frac{3}{8} = \frac{4 + 3}{8} = \frac{7}{8} This step involves adding the numerators while keeping the common denominator.

Therefore, the sum of 12 \frac{1}{2} and 38 \frac{3}{8} is 78 \frac{7}{8} .

Answer

78 \frac{7}{8}

Exercise #13

512+1136= \frac{5}{12}+\frac{11}{36}=

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify the least common denominator (LCD) of the fractions.
  • Step 2: Rewrite the fractions with the common denominator.
  • Step 3: Add the fractions.
  • Step 4: Simplify the resulting fraction.

Let's work through these steps:

Step 1: The denominators of our fractions are 12 and 36. The least common denominator is 36. This is because 36 is the smallest number that both 12 and 36 divide into evenly.

Step 2: Rewrite 512 \frac{5}{12} with the denominator 36. To do this, find what number 12 must be multiplied by to become 36, which is 3. Thus, multiply both the numerator and the denominator of 512 \frac{5}{12} by 3:

512=5×312×3=1536 \frac{5}{12} = \frac{5 \times 3}{12 \times 3} = \frac{15}{36} .

Step 3: Now add the fractions 1536 \frac{15}{36} and 1136 \frac{11}{36} , since they have a common denominator:

1536+1136=15+1136=2636 \frac{15}{36} + \frac{11}{36} = \frac{15 + 11}{36} = \frac{26}{36} .

Step 4: Simplify 2636 \frac{26}{36} . The greatest common divisor (GCD) of 26 and 36 is 2. Divide both the numerator and the denominator by 2:

2636=26÷236÷2=1318 \frac{26}{36} = \frac{26 \div 2}{36 \div 2} = \frac{13}{18} .

Therefore, the sum of 512+1136 \frac{5}{12} + \frac{11}{36} is 1318 \frac{13}{18} .

The correct choice that matches this solution is choice 4.

Answer

1318 \frac{13}{18}

Exercise #14

29+318= \frac{2}{9}+\frac{3}{18}=

Video Solution

Step-by-Step Solution

To solve this problem, we will first convert 29 \frac{2}{9} to have a denominator of 18, then proceed to add the fractions.

Step 1: Convert 29 \frac{2}{9} to have a denominator of 18.
To convert 29 \frac{2}{9} to a fraction with a denominator of 18, recognize that 18 is twice 9. Therefore, multiply both the numerator and the denominator by 2:
29=2×29×2=418\frac{2}{9} = \frac{2 \times 2}{9 \times 2} = \frac{4}{18}.

Step 2: Add the fractions 418 \frac{4}{18} and 318 \frac{3}{18} .
Since the fractions now have the same denominator, simply add the numerators:
418+318=4+318=718\frac{4}{18} + \frac{3}{18} = \frac{4 + 3}{18} = \frac{7}{18}.

There is no need to simplify further as 718 \frac{7}{18} is already in its simplest form.

The correct answer choice is 718\frac{7}{18}, which matches choice 1.

Therefore, the sum of 29\frac{2}{9} and 318\frac{3}{18} is 718\frac{7}{18}.

Answer

718 \frac{7}{18}

Exercise #15

118+16= \frac{1}{18}+\frac{1}{6}=

Video Solution

Step-by-Step Solution

To solve this problem, we need to add the fractions 118\frac{1}{18} and 16\frac{1}{6}:

Step 1: Find the least common denominator
The denominators are 18 and 6. The least common multiple of 18 and 6 is 18.

Step 2: Convert each fraction to have the least common denominator
The fraction 118\frac{1}{18} already has the denominator 18, so it remains 118\frac{1}{18}.
To convert 16\frac{1}{6} to a fraction with denominator 18, multiply both the numerator and denominator by 3: 1×36×3=318\frac{1 \times 3}{6 \times 3} = \frac{3}{18}.

Step 3: Add the converted fractions
Now that both fractions have the same denominator, add them:
118+318=1+318=418\frac{1}{18} + \frac{3}{18} = \frac{1 + 3}{18} = \frac{4}{18}.

Step 4: Simplify the resulting fraction
418\frac{4}{18} can be simplified by dividing both the numerator and the denominator by their greatest common divisor, which is 2:
4÷218÷2=29\frac{4 \div 2}{18 \div 2} = \frac{2}{9}.

Therefore, the sum of 118\frac{1}{18} and 16\frac{1}{6} is 29\frac{2}{9}.

Answer

29 \frac{2}{9}

Exercise #16

23+19= \frac{2}{3}+\frac{1}{9}=

Video Solution

Step-by-Step Solution

To solve the problem of adding 23 \frac{2}{3} and 19 \frac{1}{9} , we follow these steps:

  • Step 1: Find a common denominator.
    The denominators are 3 and 9. Since 9 is a multiple of 3, we can use 9 as the common denominator.
  • Step 2: Convert the fractions to have the common denominator.
    - To convert 23 \frac{2}{3} to have a denominator of 9, multiply both the numerator and denominator by 3: 23=2×33×3=69 \frac{2}{3} = \frac{2 \times 3}{3 \times 3} = \frac{6}{9}
  • Step 3: Add the fractions 69\frac{6}{9} and 19\frac{1}{9}.
    69+19=6+19=79 \frac{6}{9} + \frac{1}{9} = \frac{6+1}{9} = \frac{7}{9}
  • Step 4: Simplify the result, if necessary.
    The fraction 79\frac{7}{9} is already in its simplest form.

Therefore, the solution to 23+19\frac{2}{3} + \frac{1}{9} is 79\frac{7}{9}.

Answer

79 \frac{7}{9}

Exercise #17

34+220= \frac{3}{4}+\frac{2}{20}=

Video Solution

Step-by-Step Solution

To solve 34+220 \frac{3}{4} + \frac{2}{20} , let's follow these steps:

  • Step 1: Convert 34 \frac{3}{4} to a fraction with the denominator 20 20 .
    Multiply both the numerator and denominator of 34 \frac{3}{4} by 5 5 , as 20÷4=5 20 \div 4 = 5 :
    We have: 3×54×5=1520 \frac{3 \times 5}{4 \times 5} = \frac{15}{20}
  • Step 2: The fraction 220 \frac{2}{20} is already in the correct form with a denominator of 20 20 .
  • Step 3: Add the fractions 1520 \frac{15}{20} and 220 \frac{2}{20} :
    Since they have the same denominator, we combine the numerators directly: 1520+220=15+220=1720 \frac{15}{20} + \frac{2}{20} = \frac{15 + 2}{20} = \frac{17}{20}

Therefore, the sum of the fractions is 1720 \frac{17}{20} .

Answer

1720 \frac{17}{20}

Exercise #18

38+14= \frac{3}{8}+\frac{1}{4}=

Video Solution

Step-by-Step Solution

To solve the problem of adding 38 \frac{3}{8} and 14 \frac{1}{4} , we'll follow these steps:

  • Step 1: Determine the Least Common Denominator (LCD).
  • Step 2: Convert fractions to the common denominator.
  • Step 3: Add the fractions.

Let's work through each step:
Step 1: The denominators are 8 and 4. The LCD of 8 and 4 is 8, as 8 is the smallest number that both 8 and 4 divide into without a remainder.

Step 2: Convert each fraction to have the common denominator 8.
- The fraction 38 \frac{3}{8} already has the denominator 8.
- Convert 14 \frac{1}{4} to a fraction with denominator 8: 14=1×24×2=28 \frac{1}{4} = \frac{1 \times 2}{4 \times 2} = \frac{2}{8} .

Step 3: Add the fractions 38 \frac{3}{8} and 28 \frac{2}{8} :
The sum is 3+28=58 \frac{3 + 2}{8} = \frac{5}{8} .

Therefore, the solution to the problem is 58 \frac{5}{8} .

Answer

58 \frac{5}{8}

Exercise #19

115+25= \frac{1}{15}+\frac{2}{5}=

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Determine the least common denominator (LCD) of the fractions.

  • Step 2: Convert each fraction to have the common denominator.

  • Step 3: Add the numerators and keep the denominator the same.

Now, let's work through each step:

Step 1: The least common denominator of 15 and 5 is 15.

Step 2: Convert the fraction 25 \frac{2}{5} to have the denominator of 15.
To convert 25 \frac{2}{5} , we need to multiply both the numerator and the denominator by 3, because 5×3=15 {5 \times 3 = 15} .
Thus, 25=2×35×3=615 \frac{2}{5} = \frac{2 \times 3}{5 \times 3} = \frac{6}{15} .

Step 3: Now, add the fractions 115 \frac{1}{15} and 615 \frac{6}{15} .
When adding these fractions, the equation is 115+615=1+615=715 \frac{1}{15} + \frac{6}{15} = \frac{1 + 6}{15} = \frac{7}{15} .

Therefore, the solution to the problem is 715 \frac{7}{15} .

Answer

715 \frac{7}{15}

Exercise #20

415+25= \frac{4}{15}+\frac{2}{5}=

Video Solution

Step-by-Step Solution

To solve the problem of adding 415+25\frac{4}{15} + \frac{2}{5}, follow these steps:

  • Step 1: Identify a common denominator. Since 5 is a factor of 15, we will use 15 as the common denominator.
  • Step 2: Convert 25\frac{2}{5} to a fraction with a denominator of 15. To do this, multiply both the numerator and denominator by 3: 2×35×3=615\frac{2 \times 3}{5 \times 3} = \frac{6}{15}.
  • Step 3: Add the fractions: 415+615\frac{4}{15} + \frac{6}{15}.
  • Step 4: Since both fractions now have the same denominator, add the numerators: 4+615=1015\frac{4 + 6}{15} = \frac{10}{15}.
  • Step 5: Simplify 1015\frac{10}{15} by dividing both the numerator and the denominator by their greatest common divisor, which is 5: 10÷515÷5=23\frac{10 \div 5}{15 \div 5} = \frac{2}{3}.

Therefore, the sum of 415+25\frac{4}{15} + \frac{2}{5} is 23\frac{2}{3}.

Answer

23 \frac{2}{3}