Examples with solutions for Addition of Fractions: The common denominator is smaller than the product of the denominators

Exercise #1

Solve the following equation:

14+36= \frac{1}{4}+\frac{3}{6}=

Video Solution

Step-by-Step Solution

We must first identify the lowest common denominator between 4 and 6.

In order to determine the lowest common denominator, we need to find a number that is divisible by both 4 and 6.

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 2

1×34×3+3×26×2=312+612 \frac{1\times3}{4\times3}+\frac{3\times2}{6\times2}=\frac{3}{12}+\frac{6}{12}

Finally we'll combine and obtain the following:

6+312=912 \frac{6+3}{12}=\frac{9}{12}

Answer

912 \frac{9}{12}

Exercise #2

48+410= \frac{4}{8}+\frac{4}{10}=

Video Solution

Step-by-Step Solution

Let's try to find the lowest common multiple between 8 and 10

To find the lowest common multiple, we need to find a number that is divisible by both 8 and 10

In this case, the lowest common multiple is 40

Now, let's multiply each number in the appropriate multiples to reach the number 40

We will multiply the first number by 5

We will multiply the second number by 4

4×58×5+4×410×4=2040+1640 \frac{4\times5}{8\times5}+\frac{4\times4}{10\times4}=\frac{20}{40}+\frac{16}{40}

Now let's calculate:

20+1640=3640 \frac{20+16}{40}=\frac{36}{40}

Answer

3640 \frac{36}{40}

Exercise #3

Solve the following equation:

36+39= \frac{3}{6}+\frac{3}{9}=

Video Solution

Step-by-Step Solution

We must first identify the lowest common denominator between 6 and 9.

In order to determine the lowest common denominator, we need to find a number that is divisible by both 6 and 9.

In this case, the common denominator is 18.

We will then proceed to multiply each fraction by the appropriate number to reach the denominator 18.

We'll multiply the first fraction by 3

We'll multiply the second fraction by 2

3×36×3+3×29×2=918+618 \frac{3\times3}{6\times3}+\frac{3\times2}{9\times2}=\frac{9}{18}+\frac{6}{18}

Finally we'll combine and obtain the following:

9+618=1518 \frac{9+6}{18}=\frac{15}{18}

Answer

1518 \frac{15}{18}

Exercise #4

Solve the following equation:

48+512= \frac{4}{8}+\frac{5}{12}=

Video Solution

Step-by-Step Solution

Let's first identify the lowest common denominator between 8 and 12.

In order to identify the lowest common denominator, we need to find a number that is divisible by both 8 and 12.

In this case, the common denominator is 24.

Let's proceed to multiply each fraction by the appropriate number to reach the denominator 24.

We'll multiply the first fraction by 3

We'll multiply the second fraction by 2

4×38×3+5×212×2=1224+1024 \frac{4\times3}{8\times3}+\frac{5\times2}{12\times2}=\frac{12}{24}+\frac{10}{24}

Now let's add:

12+1024=2224 \frac{12+10}{24}=\frac{22}{24}

Answer

2224 \frac{22}{24}

Exercise #5

Solve the following equation:

28+512= \frac{2}{8}+\frac{5}{12}=

Video Solution

Step-by-Step Solution

Let's first identify the lowest common denominator between 8 and 12.

In order to determine the lowest common denominator, we need to find a number that is divisible by both 8 and 12.

In this case, the common denominator is 24

Now we'll proceed to multiply each fraction by the appropriate number to reach the denominator 24.p

We'll multiply the first fraction by 3

We'll multiply the second fraction by 2

2×38×3+5×212×2=624+1024 \frac{2\times3}{8\times3}+\frac{5\times2}{12\times2}=\frac{6}{24}+\frac{10}{24}

Now let's combine:

6+1024=1624 \frac{6+10}{24}=\frac{16}{24}

Answer

1624 \frac{16}{24}

Exercise #6

Solve the following equation:

410+512= \frac{4}{10}+\frac{5}{12}=

Video Solution

Step-by-Step Solution

Let's first identify the lowest common denominator between 10 and 12.

In order to determine the lowest common denominator, we need to find a number that is divisible by both 10 and 12.

In this case, the common denominator is 60.

We'll proceed to multiply each fraction by the appropriate number to reach the denominator 60.

We'll multiply the first fraction by 6

We'll multiply the second fraction by 5

4×610×6+5×512×5=2460+2560 \frac{4\times6}{10\times6}+\frac{5\times5}{12\times5}=\frac{24}{60}+\frac{25}{60}

Now let's add:

24+2560=4960 \frac{24+25}{60}=\frac{49}{60}

Answer

4960 \frac{49}{60}

Exercise #7

35+310= \frac{3}{5}+\frac{3}{10}=

Video Solution

Step-by-Step Solution

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

  • Step 1: Identify the given fractions, 35 \frac{3}{5} and 310 \frac{3}{10} .
  • Step 2: Find the least common denominator (LCD) of the denominators 5 and 10.
  • Step 3: Convert each fraction to have this common denominator.
  • Step 4: Add the fractions.

Now, let's work through each step:

Step 1: We have the fractions 35 \frac{3}{5} and 310 \frac{3}{10} .

Step 2: Check the denominators. The denominators are 5 and 10. The least common multiple of 5 and 10 is 10. Thus, our common denominator will be 10.

Step 3: Convert each fraction to an equivalent fraction with a denominator of 10:
35 \frac{3}{5} is equivalent to 3×25×2=610 \frac{3 \times 2}{5 \times 2} = \frac{6}{10} (since 510 \frac{5}{10} must equal 10, multiply both numerator and denominator by 2).

Step 4: The fraction 310 \frac{3}{10} already has the denominator of 10.
Thus, 35+310=610+310=6+310=910 \frac{3}{5} + \frac{3}{10} = \frac{6}{10} + \frac{3}{10} = \frac{6 + 3}{10} = \frac{9}{10} .

Therefore, the answer to the problem is 910 \frac{9}{10} , which corresponds to choice 1.

Answer

910 \frac{9}{10}

Exercise #8

23+79= \frac{2}{3}+\frac{7}{9}=

Video Solution

Step-by-Step Solution

To solve this problem, we will perform the following steps:

  • Step 1: Find the Least Common Multiple (LCM) of the denominators 3 and 9.
  • Step 2: Convert both fractions to have a common denominator.
  • Step 3: Add the numerators of the converted fractions and write the result over the common denominator.
  • Step 4: Simplify the resultant fraction if needed.

Let's work through each step:

Step 1:
The denominators of our fractions are 3 and 9. The LCM of 3 and 9 is 9, since 9 is the smallest number that both 3 and 9 divide evenly into.

Step 2:
Convert each fraction to have a denominator of 9.

- For 23 \frac{2}{3} , multiply both the numerator and denominator by 3 (because 93=3 \frac{9}{3} = 3 ):
23=2×33×3=69 \frac{2}{3} = \frac{2 \times 3}{3 \times 3} = \frac{6}{9}

- The second fraction 79 \frac{7}{9} already has a denominator of 9, so it remains the same:
79 \frac{7}{9}

Step 3:
Add the two fractions:
69+79=6+79=139 \frac{6}{9} + \frac{7}{9} = \frac{6 + 7}{9} = \frac{13}{9}

Step 4:
The fraction 139 \frac{13}{9} is in its simplest form because 13 is a prime number and does not divide evenly into 9.

Therefore, the solution to the problem is 139 \frac{13}{9} .

Answer

139 \frac{13}{9}

Exercise #9

910+25= \frac{9}{10}+\frac{2}{5}=

Video Solution

Step-by-Step Solution

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

  • Step 1: Identify the Least Common Denominator (LCD) for the two fractions.
  • Step 2: Convert each fraction to have the LCD as the denominator.
  • Step 3: Add the fractions with the common denominator.

Now, let's work through each step:

Step 1: The denominators of the fractions are 10 and 5. The LCD of 10 and 5 is 10.
Step 2: Convert 25\frac{2}{5} to have a denominator of 10. We can multiply both 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 3: Now, add 910\frac{9}{10} and 410\frac{4}{10} (since both fractions now have the same denominator): 910+410=9+410=1310 \frac{9}{10} + \frac{4}{10} = \frac{9 + 4}{10} = \frac{13}{10} .

The two fractions added together give us 1310 \frac{13}{10} . Therefore, the solution to the problem is 1310 \frac{13}{10} , which matches the correct answer choice.

Answer

1310 \frac{13}{10}

Exercise #10

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

Video Solution

Step-by-Step Solution

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

  • Step 1: Identify the least common multiple (LCM) of the denominators 8 and 4.
  • Step 2: Convert 14\frac{1}{4} to a fraction with the denominator of 8.
  • Step 3: Add the fractions 38\frac{3}{8} and 28\frac{2}{8}.

Now, let's work through each step:
Step 1: The LCM of 8 and 4 is 8, so this will be the common denominator.
Step 2: Transform 14\frac{1}{4} into a fraction with the denominator of 8. Multiply the numerator and the denominator by 2 to get 28\frac{2}{8}.
Step 3: Now, add the fractions with the same denominator: 38+28=58\frac{3}{8} + \frac{2}{8} = \frac{5}{8}.

Therefore, the sum of 38\frac{3}{8} and 14\frac{1}{4} is 58\frac{5}{8}, which matches choice 4.

Answer

58 \frac{5}{8}

Exercise #11

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

Video Solution

Step-by-Step Solution

To solve the problem 415+25 \frac{4}{15} + \frac{2}{5} , we will add these fractions by finding a common denominator.

Step 1: Find the Least Common Denominator (LCD).
The denominators are 15 and 5. The LCM of 15 and 5 is 15, as 15 is already a multiple of 5.

Step 2: Convert each fraction to have the same denominator, 15.
- The fraction 415 \frac{4}{15} already has the denominator 15. - Convert 25 \frac{2}{5} to a fraction with a denominator of 15 by multiplying 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 with common denominators.
Now we have: 415+615 \frac{4}{15} + \frac{6}{15} .
Add the numerators: 4+6=10 4 + 6 = 10 .
The new fraction is 1015 \frac{10}{15} .

Step 4: Simplify the resulting fraction, if possible.
Both 10 and 15 are divisible by 5.
Divide the numerator and the denominator by their greatest common divisor (GCD), which is 5: 10÷515÷5=23 \frac{10 \div 5}{15 \div 5} = \frac{2}{3} .

The solution to the problem is 23 \frac{2}{3} .

Answer

23 \frac{2}{3}

Exercise #12

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

Video Solution

Step-by-Step Solution

We need to find a common denominator for the fractions 13\frac{1}{3} and 16\frac{1}{6} in order to add them together.

Step 1: Identify the least common denominator (LCD).

  • The denominators are 3 and 6.
  • The least common multiple (LCM) of 3 and 6 is 6. Hence, the LCD is 6.

Step 2: Convert each fraction to an equivalent fraction with the LCD of 6.

  • 13\frac{1}{3} needs to be converted. Multiply both numerator and denominator by 2: 13=1×23×2=26\frac{1}{3} = \frac{1 \times 2}{3 \times 2} = \frac{2}{6}.
  • 16\frac{1}{6} already has the denominator as 6, so it remains 16\frac{1}{6}.

Step 3: Add the fractions.

  • Now that the denominators are the same, we can add the numerators: 26+16=2+16=36\frac{2}{6} + \frac{1}{6} = \frac{2 + 1}{6} = \frac{3}{6}.

Step 4: Simplify the result.

  • 36\frac{3}{6} can be simplified by dividing both the numerator and the denominator by their greatest common divisor (GCD), which is 3: 36=3÷36÷3=12\frac{3}{6} = \frac{3 \div 3}{6 \div 3} = \frac{1}{2}.

Thus, the result of the addition of 13\frac{1}{3} and 16\frac{1}{6} is 12\frac{1}{2}.

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

Answer

12 \frac{1}{2}

Exercise #13

314+37= \frac{3}{14}+\frac{3}{7}=

Video Solution

Step-by-Step Solution

To solve the problem of adding 314+37 \frac{3}{14} + \frac{3}{7} , we need the following steps:

  • Step 1: Identify the least common denominator of 14 14 and 7 7 . Since 7 7 is a factor of 14 14 , the least common denominator is 14 14 .
  • Step 2: Rewrite the fractions with the common denominator.
    The fraction 37 \frac{3}{7} can be converted to an equivalent fraction with the denominator 14 14 :
    • Multiply the numerator and the denominator of 37 \frac{3}{7} by 2 2 (since 7×2=14 7 \times 2 = 14 ) to get 614 \frac{6}{14} .
  • Step 3: Add 314 \frac{3}{14} and 614 \frac{6}{14} now that they have the same denominator:
    314+614=3+614=914\frac{3}{14} + \frac{6}{14} = \frac{3+6}{14} = \frac{9}{14}.
  • Step 4: Simplify if necessary. The numerator and denominator here are coprime, so 914 \frac{9}{14} is already in its simplest form.

Thus, the sum of the fractions is 914 \frac{9}{14} .

Answer

914 \frac{9}{14}

Exercise #14

34+38= \frac{3}{4}+\frac{3}{8}=

Video Solution

Step-by-Step Solution

To solve the problem of adding 34 \frac{3}{4} and 38 \frac{3}{8} , let's follow a systematic approach:

  • Step 1: Identify the Common Denominator
    The denominators are 4 and 8. The least common multiple (LCM) of 4 and 8 is 8. Thus, 8 will be our common denominator.
  • Step 2: Convert Fractions to Common Denominator
    The fraction 34 \frac{3}{4} needs to be converted to an equivalent fraction with a denominator of 8. To do this, multiply both the numerator and the denominator by 2: 34=3×24×2=68 \frac{3}{4} = \frac{3 \times 2}{4 \times 2} = \frac{6}{8} .
    The fraction 38 \frac{3}{8} already has a denominator of 8, so it remains the same: 38 \frac{3}{8} .
  • Step 3: Add the Fractions
    With a common denominator, add the numerators while keeping the denominator the same: 68+38=6+38=98 \frac{6}{8} + \frac{3}{8} = \frac{6 + 3}{8} = \frac{9}{8} .
  • Step 4: Simplify the Fraction if Necessary
    The fraction 98 \frac{9}{8} is already in its simplest form, but it is an improper fraction. If desired, it can be expressed as a mixed number: 118 1 \frac{1}{8} . However, 98 \frac{9}{8} as a fraction suffices for this problem.

Therefore, the solution to the problem is 98 \frac{9}{8} .

Answer

98 \frac{9}{8}

Exercise #15

34+16= \frac{3}{4}+\frac{1}{6}=

Video Solution

Step-by-Step Solution

To solve the problem of adding the fractions 34\frac{3}{4} and 16\frac{1}{6}, we need to find a common denominator.

  • Step 1: Find the LCM of the denominators:
    The denominators are 4 and 6. The LCM of 4 and 6 is 12.
  • Step 2: Convert each fraction to have the common denominator:
    - Convert 34\frac{3}{4} to an equivalent fraction with a denominator of 12. To do this, multiply both the numerator and the denominator by 3:
    34=3×34×3=912\frac{3}{4} = \frac{3 \times 3}{4 \times 3} = \frac{9}{12}.
    - Convert 16\frac{1}{6} to an equivalent fraction with a denominator of 12. Multiply both the numerator and the denominator by 2:
    16=1×26×2=212\frac{1}{6} = \frac{1 \times 2}{6 \times 2} = \frac{2}{12}.
  • Step 3: Add the fractions:
    Now that both fractions have the same denominator, add the numerators:
    912+212=1112\frac{9}{12} + \frac{2}{12} = \frac{11}{12}.
  • Step 4: Simplify if necessary:
    The fraction 1112\frac{11}{12} is already in its simplest form.

Therefore, the solution to the problem 34+16\frac{3}{4} + \frac{1}{6} is 1112\frac{11}{12}.

Answer

1112 \frac{11}{12}

Exercise #16

12+46= \frac{1}{2}+\frac{4}{6}=

Video Solution

Step-by-Step Solution

To solve the problem of adding the fractions 12\frac{1}{2} and 46\frac{4}{6}, we start by finding the least common denominator (LCD).

First, we identify the denominators: 2 and 6. The least common multiple of 2 and 6 is 6, which will be our LCD.

Next, we convert each fraction to have the denominator of 6:

  • Convert 12\frac{1}{2} to an equivalent fraction with a denominator of 6. Since 23=62 \cdot 3 = 6, multiply the numerator by 3: 1×32×3=36\frac{1 \times 3}{2 \times 3} = \frac{3}{6}.

  • The fraction 46\frac{4}{6} already has the desired common denominator.

Now that the fractions are 36\frac{3}{6} and 46\frac{4}{6}, we can add them:

36+46=3+46=76\frac{3}{6} + \frac{4}{6} = \frac{3+4}{6} = \frac{7}{6}.

The solution to the problem is 76\frac{7}{6}, which matches choice 2.

Answer

76 \frac{7}{6}

Exercise #17

14+78= \frac{1}{4}+\frac{7}{8}=

Video Solution

Step-by-Step Solution

To find the sum 14+78 \frac{1}{4} + \frac{7}{8} , follow these steps:

  • Step 1: Identify the least common denominator (LCD) of the fractions. The denominators 4 and 8 have an LCD of 8.
  • Step 2: Convert 14 \frac{1}{4} to an equivalent fraction with a denominator of 8. Multiply both the numerator and the denominator by 2: 14=1×24×2=28 \frac{1}{4} = \frac{1 \times 2}{4 \times 2} = \frac{2}{8} .
  • Step 3: The second fraction, 78 \frac{7}{8} , already has the correct denominator. Therefore, it remains 78 \frac{7}{8} .
  • Step 4: Add the numerators of the two fractions: 28+78=2+78=98 \frac{2}{8} + \frac{7}{8} = \frac{2+7}{8} = \frac{9}{8} .

Therefore, the sum of 14 \frac{1}{4} and 78 \frac{7}{8} is 98 \frac{9}{8} .

Answer

98 \frac{9}{8}

Exercise #18

14+34= \frac{1}{4}+\frac{3}{4}=

Video Solution

Step-by-Step Solution

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

  • Step 1: Identify the denominators of the fractions.
  • Step 2: Because the denominators are the same, add the numerators.
  • Step 3: Simplify the resulting fraction if necessary.

Now, let's work through each step:
Step 1: Both fractions, 14 \frac{1}{4} and 34 \frac{3}{4} , have the same denominator, 4.
Step 2: Since the denominators are the same, we can add the numerators: 1+3=4 1 + 3 = 4 .
Step 3: The resulting fraction is 44 \frac{4}{4} , which simplifies to 1 1 .

Therefore, the solution to the problem is 1 1 .

Answer

1 1

Exercise #19

12+16= \frac{1}{2}+\frac{1}{6}=

Video Solution

Step-by-Step Solution

To solve the problem of adding 12 \frac{1}{2} and 16 \frac{1}{6} , we need to follow these steps:

  • Step 1: Determine the least common denominator (LCD).
  • Step 2: Convert the fractions to have this common denominator.
  • Step 3: Add the fractions.
  • Step 4: Simplify the result if necessary.

Step 1: The denominators are 2 and 6. The least common multiple of 2 and 6 is 6.

Step 2: We convert each fraction:
- Convert 12 \frac{1}{2} to a denominator of 6: 12=1×32×3=36\frac{1}{2} = \frac{1 \times 3}{2 \times 3} = \frac{3}{6}.
- The fraction 16 \frac{1}{6} already has the denominator 6.

Step 3: Add the fractions with common denominators:
36+16=3+16=46. \frac{3}{6} + \frac{1}{6} = \frac{3 + 1}{6} = \frac{4}{6}.

Step 4: Simplify the fraction 46\frac{4}{6}.
The greatest common divisor of 4 and 6 is 2, so divide both the numerator and the denominator by 2:
46=4÷26÷2=23. \frac{4}{6} = \frac{4 \div 2}{6 \div 2} = \frac{2}{3}.

Therefore, the solution to the problem is 23\frac{2}{3}.

Answer

23 \frac{2}{3}

Exercise #20

46+18= \frac{4}{6}+\frac{1}{8}=

Video Solution

Step-by-Step Solution

To solve the addition of the fractions 46+18 \frac{4}{6} + \frac{1}{8} , we will first find the least common denominator.

  • The denominators of the fractions are 6 and 8. To add these fractions, we need a common denominator.
  • Calculate the least common multiple (LCM) of 6 and 8:
    • Prime factorization of 6: 6=2×3 6 = 2 \times 3 .
    • Prime factorization of 8: 8=23 8 = 2^3 .
    • The LCM will take the highest power of each prime that appears in these factorizations: 23×3=24 2^3 \times 3 = 24 .
  • Convert each fraction to an equivalent fraction with 24 as the denominator:
    • Convert 46 \frac{4}{6} : Multiply both the numerator and denominator by 4 (since 246=4 \frac{24}{6} = 4 ): 4×46×4=1624\frac{4 \times 4}{6 \times 4} = \frac{16}{24}.
    • Convert 18 \frac{1}{8} : Multiply both the numerator and denominator by 3 (since 248=3 \frac{24}{8} = 3 ): 1×38×3=324\frac{1 \times 3}{8 \times 3} = \frac{3}{24}.
  • Now, add these two fractions:
    • 1624+324=16+324=1924\frac{16}{24} + \frac{3}{24} = \frac{16 + 3}{24} = \frac{19}{24}.

Thus, the sum of the fractions 46 \frac{4}{6} and 18 \frac{1}{8} is 1924\frac{19}{24}.

The correct choice from the available options is 1924\frac{19}{24}.

Therefore, the solution to the problem is 1924 \frac{19}{24} .

Answer

1924 \frac{19}{24}