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

Exercise #1

Solve the following exercise:

15+215= \frac{1}{5}+\frac{2}{15}=

Video Solution

Step-by-Step Solution

Let's try to find the lowest common denominator between 5 and 15

To find the lowest common denominator, we need to find a number that is divisible by both 5 and 15

In this case, the common denominator is 15

Now we'll multiply each fraction by the appropriate number to reach the denominator 15

We'll multiply the first fraction by 3

We'll multiply the second fraction by 1

1×35×3+2×115×1=315+215 \frac{1\times3}{5\times3}+\frac{2\times1}{15\times1}=\frac{3}{15}+\frac{2}{15}

Now we'll combine and get:

3+215=515 \frac{3+2}{15}=\frac{5}{15}

Answer

515 \frac{5}{15}

Exercise #2

Solve the following exercise:

13+16=? \frac{1}{3}+\frac{1}{6}=\text{?}

Video Solution

Step-by-Step Solution

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

  • Identify the common denominator.
  • Convert each fraction to an equivalent fraction with the common denominator.
  • Add the fractions.
  • Verify the solution against given choices.

Now, let's work through each step:

Step 1: Identify the common denominator. For fractions 13 \frac{1}{3} and 16 \frac{1}{6} , the least common multiple (LCM) of 3 and 6 is 6.

Step 2: Convert 13 \frac{1}{3} to have a denominator of 6. We do this by multiplying both the numerator and denominator by 2:

13=1×23×2=26 \frac{1}{3} = \frac{1 \times 2}{3 \times 2} = \frac{2}{6}

The fraction 16 \frac{1}{6} already has a denominator of 6, so we leave it unchanged:

16=16 \frac{1}{6} = \frac{1}{6}

Step 3: Add the fractions:

26+16=2+16=36 \frac{2}{6} + \frac{1}{6} = \frac{2 + 1}{6} = \frac{3}{6}

The fraction 36 \frac{3}{6} simplifies to 12 \frac{1}{2} , but since the task is to match with given choices, we note that there is no need to simplify further.

After comparing with the given choices, the option that matches our calculation is:

36 \frac{3}{6}

Answer

36 \frac{3}{6}

Exercise #3

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 #4

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 #5

Solve the following exercise:

14+48=? \frac{1}{4}+\frac{4}{8}=\text{?}

Video Solution

Step-by-Step Solution

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

  • Step 1: Convert 14 \frac{1}{4} to a fraction with a denominator of 8.
  • Step 2: Add the fractions.
  • Step 3: Simplify the result.

Now, let's work through each step:

Step 1: Convert 14 \frac{1}{4} to have a denominator of 8. Since 8÷4=2 8 \div 4 = 2 , multiply both the numerator and denominator of 14 \frac{1}{4} by 2:

14=1×24×2=28 \frac{1}{4} = \frac{1 \times 2}{4 \times 2} = \frac{2}{8}

Step 2: Now add 28 \frac{2}{8} and 48 \frac{4}{8} :

28+48=2+48=68 \frac{2}{8} + \frac{4}{8} = \frac{2 + 4}{8} = \frac{6}{8}

Step 3: Simplify 68 \frac{6}{8} if possible. The greatest common divisor of 6 and 8 is 2. So, 68 \frac{6}{8} simplifies to:

6÷28÷2=34 \frac{6 \div 2}{8 \div 2} = \frac{3}{4}

Therefore, the solution to the problem is 68 \frac{6}{8} .

Answer

68 \frac{6}{8}

Exercise #6

Solve the following exercise:

12+310=? \frac{1}{2}+\frac{3}{10}=\text{?}

Video Solution

Step-by-Step Solution

To solve the problem, follow these steps:

  • Step 1: Recognize the denominators 22 and 1010 and note that 1010 is a common multiple.
  • Step 2: Convert 12\frac{1}{2} to a fraction with a denominator of 10. Since 2×5=102 \times 5 = 10, multiply both the numerator and denominator of 12\frac{1}{2} by 5 to get 510\frac{5}{10}.
  • Step 3: The second fraction, 310\frac{3}{10}, already has a denominator of 10, so no conversion is needed.
  • Step 4: Add the two fractions: 510+310\frac{5}{10} + \frac{3}{10}.
  • Step 5: As the denominators are the same, add the numerators: 5+3=85 + 3 = 8.
  • Step 6: Write the result with the common denominator: 810\frac{8}{10}.
  • Step 7: Check if the fraction can be simplified further. Since 8 and 10 have a common factor of 2, divide by 2 to simplify: 810=45\frac{8}{10} = \frac{4}{5}.

The problem's correct answer without simplification matches choice 1.

Therefore, the solution to the problem is 810 \frac{8}{10} .

Answer

810 \frac{8}{10}

Exercise #7

Solve the following exercise:

12+28=? \frac{1}{2}+\frac{2}{8}=\text{?}

Video Solution

Step-by-Step Solution

To solve this problem, we will follow these steps:

  • Step 1: Identify the given fractions 12\frac{1}{2} and 28\frac{2}{8}.
  • Step 2: Determine a common denominator for both fractions. Since 8 is a multiple of 2, we will use 8 as the common denominator.
  • Step 3: Convert 12\frac{1}{2} to an equivalent fraction with a denominator of 8.
  • Step 4: Add the fractions together.

Now, let's work through these steps:

Step 1: The fractions given are 12\frac{1}{2} and 28\frac{2}{8}.

Step 2: We choose 8 as the common denominator because it is a multiple of 2.

Step 3: Convert 12\frac{1}{2} to have a denominator of 8. To do this, multiply both the numerator and the denominator of 12\frac{1}{2} by 4:

12=1×42×4=48 \frac{1}{2} = \frac{1 \times 4}{2 \times 4} = \frac{4}{8}

The fractions now are 48\frac{4}{8} and 28\frac{2}{8}, both having the common denominator 8.

Step 4: Add the numerators of these fractions:

48+28=4+28=68 \frac{4}{8} + \frac{2}{8} = \frac{4+2}{8} = \frac{6}{8}

Therefore, the sum of 12+28\frac{1}{2} + \frac{2}{8} is 68 \frac{6}{8} .

Answer

68 \frac{6}{8}

Exercise #8

Solve the following exercise:

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

Video Solution

Step-by-Step Solution

To solve the problem of adding 23 \frac{2}{3} and 16 \frac{1}{6} , we will first find a common denominator:

  • Step 1: Identify the least common denominator (LCD), which is 6 for the fractions 23 \frac{2}{3} and 16 \frac{1}{6} .
  • Step 2: Convert 23 \frac{2}{3} to an equivalent fraction with a denominator of 6. To do this, multiply both the numerator and the denominator by 2: 23=2×23×2=46 \frac{2}{3} = \frac{2 \times 2}{3 \times 2} = \frac{4}{6}
  • Step 3: Now, add the fractions 46 \frac{4}{6} and 16 \frac{1}{6} : 46+16=4+16=56 \frac{4}{6} + \frac{1}{6} = \frac{4 + 1}{6} = \frac{5}{6}

As we see, both fractions have been added correctly. The sum is already in its simplest form.

Therefore, the solution to the problem is 56 \frac{5}{6} .

Answer

56 \frac{5}{6}

Exercise #9

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 #10

Solve the following exercise:

16+412=? \frac{1}{6}+\frac{4}{12}=\text{?}

Video Solution

Step-by-Step Solution

To solve the problem of adding 16+412 \frac{1}{6} + \frac{4}{12} , follow these steps:

  • Step 1: Find the least common denominator (LCD) for the fractions. The denominators are 6 and 12, and the LCD is 12.
  • Step 2: Convert 16 \frac{1}{6} to an equivalent fraction with a denominator of 12. To do this, multiply both the numerator and the denominator by 2: 16×22=212 \frac{1}{6} \times \frac{2}{2} = \frac{2}{12} .
  • Step 3: The fraction 412 \frac{4}{12} already has the denominator of 12, so no conversion is needed.
  • Step 4: Add the fractions with the common denominator: 212+412=612 \frac{2}{12} + \frac{4}{12} = \frac{6}{12} .
  • Step 5: Simplify the resulting fraction if possible. In this case, 612 \frac{6}{12} simplifies to 12 \frac{1}{2} , but we will leave it as 612 \frac{6}{12} as it appears in the options.

Therefore, the solution to the problem is 612 \frac{6}{12} , which matches option 3 from the provided answers.

Answer

612 \frac{6}{12}

Exercise #11

Solve the following exercise:

25+510=? \frac{2}{5}+\frac{5}{10}=\text{?}

Video Solution

Step-by-Step Solution

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

  • Step 1: Convert the fractions to have the same denominator.
  • Step 2: Add the fractions.
  • Step 3: Simplify the resulting fraction.

Let's proceed with solving the problem:

Step 1: Convert 25 \frac{2}{5} to a fraction with a denominator of 10. The equivalent fraction is found by multiplying the numerator and the denominator by 2:

25=2×25×2=410 \frac{2}{5} = \frac{2 \times 2}{5 \times 2} = \frac{4}{10}

Step 2: Add the fractions 410 \frac{4}{10} and 510 \frac{5}{10} :

410+510=4+510=910 \frac{4}{10} + \frac{5}{10} = \frac{4 + 5}{10} = \frac{9}{10}

Step 3: Simplify the resulting fraction. Since 910\frac{9}{10} is already in its simplest form, we conclude:

Therefore, the solution to the problem is 910\frac{9}{10}.

Answer

910 \frac{9}{10}

Exercise #12

Solve the following exercise:

35+415=? \frac{3}{5}+\frac{4}{15}=\text{?}

Video Solution

Step-by-Step Solution

To solve the problem of adding 35+415 \frac{3}{5} + \frac{4}{15} , we follow these steps:

  • Step 1: Identify a common denominator for the fractions. Since 15 is a multiple of 5, we can use 15 as the common denominator.
  • Step 2: Convert 35 \frac{3}{5} to an equivalent fraction with a denominator of 15.
  • Step 3: Add the fractions once they have a common denominator.
  • Step 4: Simplify the result if possible.

Let's solve each step:
Step 1: Our common denominator is 15.
Step 2: To convert 35 \frac{3}{5} to a fraction with a denominator of 15, multiply both the numerator and the denominator by 3:
35=3×35×3=915 \frac{3}{5} = \frac{3 \times 3}{5 \times 3} = \frac{9}{15} .
Step 3: Now add 915 \frac{9}{15} and 415 \frac{4}{15} :
915+415=9+415=1315 \frac{9}{15} + \frac{4}{15} = \frac{9 + 4}{15} = \frac{13}{15} .
Step 4: The fraction 1315\frac{13}{15} is already in its simplest form.

Therefore, the solution to the problem is 1315\frac{13}{15}.

Answer

1315 \frac{13}{15}

Exercise #13

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 #14

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 #15

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 #16

312+14= \frac{3}{12}+\frac{1}{4}=

Video Solution

Step-by-Step Solution

To solve this problem, we'll take the following steps:

  • Step 1: Convert 14 \frac{1}{4} to an equivalent fraction with a denominator of 12.
    Since 4×3=12 4 \times 3 = 12 , multiply both the numerator and the denominator of 14 \frac{1}{4} by 3 to get 312 \frac{3}{12} .
  • Step 2: Add 312+312 \frac{3}{12} + \frac{3}{12} .
    The numerators will add to 3+3 3 + 3 , giving 612 \frac{6}{12} .
  • Step 3: Simplify the fraction 612 \frac{6}{12} .
    The greatest common divisor of 6 and 12 is 6, so divide both the numerator and the denominator by 6 to get 12 \frac{1}{2} .

Therefore, the solution to the problem is 12 \frac{1}{2} .

Answer

12 \frac{1}{2}

Exercise #17

Solve the following exercise:

35+215= \frac{3}{5}+\frac{2}{15}=

Video Solution

Step-by-Step Solution

Let's try to find the lowest common denominator between 5 and 15

To find the lowest common denominator, we need to find a number that is divisible by both 5 and 15

In this case, the common denominator is 15

Now we'll multiply each fraction by the appropriate number to reach the denominator 15

We'll multiply the first fraction by 3

We'll multiply the second fraction by 1

3×35×3+2×115×1=915+215 \frac{3\times3}{5\times3}+\frac{2\times1}{15\times1}=\frac{9}{15}+\frac{2}{15}

Now we'll combine and get:

9+215=1115 \frac{9+2}{15}=\frac{11}{15}

Answer

1115 \frac{11}{15}

Exercise #18

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}

Exercise #19

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 #20

Solve the following exercise:

12+210= \frac{1}{2}+\frac{2}{10}=

Video Solution

Step-by-Step Solution

Let's try to find the lowest common denominator between 2 and 10

To find the lowest common denominator, we need to find a number that is divisible by both 2 and 10

In this case, the common denominator is 10

Now we'll multiply each fraction by the appropriate number to reach the denominator 10

We'll multiply the first fraction by 5

We'll multiply the second fraction by 1

1×52×5+2×110×1=510+210 \frac{1\times5}{2\times5}+\frac{2\times1}{10\times1}=\frac{5}{10}+\frac{2}{10}

Now we'll combine and get:

5+210=710 \frac{5+2}{10}=\frac{7}{10}

Answer

710 \frac{7}{10}