Examples with solutions for Common Denominators: More than two fractions

Exercise #1

81015210= \frac{8}{10}-\frac{1}{5}-\frac{2}{10}=

Video Solution

Step-by-Step Solution

Let's try to find the least common denominator between 10 and 5

To find the least common denominator, we need to find a number that is divisible by both 10 and 5

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 1

We'll multiply the second fraction by 2

We'll multiply the third fraction by 1

8×110×11×25×22×110×1=810210210 \frac{8\times1}{10\times1}-\frac{1\times2}{5\times2}-\frac{2\times1}{10\times1}=\frac{8}{10}-\frac{2}{10}-\frac{2}{10}

Now let's subtract:

82210=6210=410 \frac{8-2-2}{10}=\frac{6-2}{10}=\frac{4}{10}

Answer

410 \frac{4}{10}

Exercise #2

5624112= \frac{5}{6}-\frac{2}{4}-\frac{1}{12}=

Video Solution

Step-by-Step Solution

Let's try to find the lowest common denominator between 6 and 4 and 12

To find the lowest common denominator, we need to find a number that is divisible by 6, 4, and 12

In this case, the common denominator is 12

Now we'll multiply each fraction by the appropriate number to reach the denominator 12

We'll multiply the first fraction by 2

We'll multiply the second fraction by 3

We'll multiply the third fraction by 1

5×26×22×34×31×112×1=1012612112 \frac{5\times2}{6\times2}-\frac{2\times3}{4\times3}-\frac{1\times1}{12\times1}=\frac{10}{12}-\frac{6}{12}-\frac{1}{12}

Now let's subtract:

106112=4112=312 \frac{10-6-1}{12}=\frac{4-1}{12}=\frac{3}{12}

Answer

312 \frac{3}{12}

Exercise #3

41015110= \frac{4}{10}-\frac{1}{5}-\frac{1}{10}=

Video Solution

Step-by-Step Solution

Let's try to find the least common denominator between 10 and 5

To find the least common denominator, we need to find a number that is divisible by both 10 and 5

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 1

We'll multiply the second fraction by 2

We'll multiply the third fraction by 1

4×110×11×25×21×110×1=410210110 \frac{4\times1}{10\times1}-\frac{1\times2}{5\times2}-\frac{1\times1}{10\times1}=\frac{4}{10}-\frac{2}{10}-\frac{1}{10}

Now we'll subtract and get:

42110=2110=110 \frac{4-2-1}{10}=\frac{2-1}{10}=\frac{1}{10}

Answer

110 \frac{1}{10}

Exercise #4

8521523= \frac{8}{5}-\frac{2}{15}-\frac{2}{3}=

Video Solution

Step-by-Step Solution

Let's try to find the least common multiple (LCM) between 5, 15, and 3

To find the least common multiple, we need to find a number that is divisible by 5, 15, and 3

In this case, the least common multiple 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

We'll multiply the third fraction by 5

8×35×32×115×12×53×5=24152151015 \frac{8\times3}{5\times3}-\frac{2\times1}{15\times1}-\frac{2\times5}{3\times5}=\frac{24}{15}-\frac{2}{15}-\frac{10}{15}

Now let's subtract:

2421015=221015=1215 \frac{24-2-10}{15}=\frac{22-10}{15}=\frac{12}{15}

Let's divide both numerator and denominator by 3 and we get:

12:315:3=45 \frac{12:3}{15:3}=\frac{4}{5}

Answer

45 \frac{4}{5}

Exercise #5

7521523= \frac{7}{5}-\frac{2}{15}-\frac{2}{3}=

Video Solution

Step-by-Step Solution

Let's try to find the least common denominator between 5 and 15 and 3

To find the least common denominator, we need to find a number that is divisible by 5, 15, and 3

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

We'll multiply the third fraction by 5

7×35×32×115×12×53×5=21152151015 \frac{7\times3}{5\times3}-\frac{2\times1}{15\times1}-\frac{2\times5}{3\times5}=\frac{21}{15}-\frac{2}{15}-\frac{10}{15}

Now let's subtract:

2121015=191015=915 \frac{21-2-10}{15}=\frac{19-10}{15}=\frac{9}{15}

We'll divide both the numerator and denominator by 3 and get:

9:315:3=35 \frac{9:3}{15:3}=\frac{3}{5}

Answer

35 \frac{3}{5}

Exercise #6

4521015= \frac{4}{5}-\frac{2}{10}-\frac{1}{5}=

Video Solution

Step-by-Step Solution

Let's try to find the least common denominator between 10 and 5

To find the least common denominator, we need to find a number that is divisible by both 10 and 5

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 2

We'll multiply the second fraction by 1

We'll multiply the third fraction by 2

4×25×22×110×11×25×2=810210210 \frac{4\times2}{5\times2}-\frac{2\times1}{10\times1}-\frac{1\times2}{5\times2}=\frac{8}{10}-\frac{2}{10}-\frac{2}{10}

Now let's subtract:

82210=6210=410 \frac{8-2-2}{10}=\frac{6-2}{10}=\frac{4}{10}

Answer

410 \frac{4}{10}

Exercise #7

2316312= \frac{2}{3}-\frac{1}{6}-\frac{3}{12}=

Video Solution

Step-by-Step Solution

Let's try to find the least common denominator between 3, 6, and 12

To find the least common denominator, we need to find a number that is divisible by 3, 6, and 12

In this case, the common denominator is 12

Now we'll multiply each fraction by the appropriate number to reach the denominator 12

We'll multiply the first fraction by 4

We'll multiply the second fraction by 2

We'll multiply the third fraction by 1

2×43×41×26×23×112×1=812212312 \frac{2\times4}{3\times4}-\frac{1\times2}{6\times2}-\frac{3\times1}{12\times1}=\frac{8}{12}-\frac{2}{12}-\frac{3}{12}

Now let's subtract:

82312=6312=312 \frac{8-2-3}{12}=\frac{6-3}{12}=\frac{3}{12}

Let's divide both numerator and denominator by 3 and we get:

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

Answer

14 \frac{1}{4}

Exercise #8

426814= \frac{4}{2}-\frac{6}{8}-\frac{1}{4}=

Video Solution

Step-by-Step Solution

Let's try to find the least common multiple (LCM) between 2, 8, and 4

To find the least common multiple, we need to find a number that is divisible by 2, 8, and 4

In this case, the least common multiple is 8

Now we'll multiply each fraction by the appropriate number to reach a denominator of 8

We'll multiply the first fraction by 4

We'll multiply the second fraction by 1

We'll multiply the third fraction by 2

4×42×46×18×11×24×2=1686824 \frac{4\times4}{2\times4}-\frac{6\times1}{8\times1}-\frac{1\times2}{4\times2}=\frac{16}{8}-\frac{6}{8}-\frac{2}{4}

Now let's subtract:

16628=1028=88 \frac{16-6-2}{8}=\frac{10-2}{8}=\frac{8}{8}

We'll solve the fraction in the following way:

88=11=1 \frac{8}{8}=\frac{1}{1}=1

Answer

1 1

Exercise #9

5624312= \frac{5}{6}-\frac{2}{4}-\frac{3}{12}=

Video Solution

Step-by-Step Solution

Let's try to find the lowest common denominator between 6, 4, and 12

To find the lowest common denominator, we need to find a number that is divisible by 6, 4, and 12

In this case, the common denominator is 12

Now we'll multiply each fraction by the appropriate number to reach the denominator 12

We'll multiply the first fraction by 2

We'll multiply the second fraction by 3

We'll multiply the third fraction by 1

5×26×22×34×33×112×1=1012612312 \frac{5\times2}{6\times2}-\frac{2\times3}{4\times3}-\frac{3\times1}{12\times1}=\frac{10}{12}-\frac{6}{12}-\frac{3}{12}

Now we'll subtract and get:

106312=4312=112 \frac{10-6-3}{12}=\frac{4-3}{12}=\frac{1}{12}

Answer

112 \frac{1}{12}

Exercise #10

10122316= \frac{10}{12}-\frac{2}{3}-\frac{1}{6}=

Video Solution

Step-by-Step Solution

Let's try to find the lowest common denominator between 12, 3, and 6

To find the lowest common denominator, we need to find a number that is divisible by 12, 3, and 6

In this case, the common denominator is 12

Now we'll multiply each fraction by the appropriate number to reach the denominator 12

We'll multiply the first fraction by 1

We'll multiply the second fraction by 4

We'll multiply the third fraction by 2

10×112×12×43×41×26×2=1012812212 \frac{10\times1}{12\times1}-\frac{2\times4}{3\times4}-\frac{1\times2}{6\times2}=\frac{10}{12}-\frac{8}{12}-\frac{2}{12}

Now let's subtract:

108212=2212=012 \frac{10-8-2}{12}=\frac{2-2}{12}=\frac{0}{12}

We'll divide both the numerator and denominator by 0 and get:

012=0 \frac{0}{12}=0

Answer

0 0

Exercise #11

2316612= \frac{2}{3}-\frac{1}{6}-\frac{6}{12}=

Video Solution

Step-by-Step Solution

Let's try to find the lowest common multiple of 3, 6 and 12

To find the lowest common multiple, we find a number that is divisible by 3, 6 and 12

In this case, the common multiple is 12

Now let's multiply each number in the appropriate multiple to reach the multiple of 12

We will multiply the first number by 4

We will multiply the second number by 2

We will multiply the third number by 1

2×43×41×26×26×112×1=812212612 \frac{2\times4}{3\times4}-\frac{1\times2}{6\times2}-\frac{6\times1}{12\times1}=\frac{8}{12}-\frac{2}{12}-\frac{6}{12}

Now let's subtract:

82612=6612=012 \frac{8-2-6}{12}=\frac{6-6}{12}=\frac{0}{12}

We will divide the numerator and the denominator by 0 and get:

012=0 \frac{0}{12}=0

Answer

0 0

Exercise #12

23+21545= \frac{2}{3}+\frac{2}{15}-\frac{4}{5}=

Video Solution

Step-by-Step Solution

Let's try to find the lowest common denominator between 3, 15, and 5

To find the lowest common denominator, we need to find a number that is divisible by 3, 15, and 5

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 5

We'll multiply the second fraction by 1

We'll multiply the third fraction by 3

2×53×5+2×115×14×35×3=1015+2151215 \frac{2\times5}{3\times5}+\frac{2\times1}{15\times1}-\frac{4\times3}{5\times3}=\frac{10}{15}+\frac{2}{15}-\frac{12}{15}

Now we'll add and then subtract:

10+21215=121215=015 \frac{10+2-12}{15}=\frac{12-12}{15}=\frac{0}{15}

We'll divide both the numerator and denominator by 0 and get:

015=0 \frac{0}{15}=0

Answer

0 0

Exercise #13

1238+24= \frac{1}{2}-\frac{3}{8}+\frac{2}{4}=

Video Solution

Step-by-Step Solution

Let's try to find the least common multiple (LCM) between 2, 8, and 4

To find the least common multiple, we need to find a number that is divisible by 2, 8, and 4

In this case, the least common multiple is 8

Now we'll multiply each fraction by the appropriate number to reach the denominator 8

We'll multiply the first fraction by 4

We'll multiply the second fraction by 1

We'll multiply the third fraction by 2

1×42×43×18×1+2×24×2=4838+48 \frac{1\times4}{2\times4}-\frac{3\times1}{8\times1}+\frac{2\times2}{4\times2}=\frac{4}{8}-\frac{3}{8}+\frac{4}{8}

Now we'll subtract and then add:

43+48=1+48=58 \frac{4-3+4}{8}=\frac{1+4}{8}=\frac{5}{8}

Answer

58 \frac{5}{8}

Exercise #14

3613112= \frac{3}{6}-\frac{1}{3}-\frac{1}{12}=

Video Solution

Step-by-Step Solution

Let's try to find the least common denominator between 6, 3, and 12

To find the least common denominator, we need to find a number that is divisible by 6, 3, and 12

In this case, the common denominator is 12

Now we'll multiply each fraction by the appropriate number to reach the denominator 12

We'll multiply the first fraction by 2

We'll multiply the second fraction by 4

We'll multiply the third fraction by 1

3×26×21×43×41×112×1=612412112 \frac{3\times2}{6\times2}-\frac{1\times4}{3\times4}-\frac{1\times1}{12\times1}=\frac{6}{12}-\frac{4}{12}-\frac{1}{12}

Now let's subtract:

64112=2112=112 \frac{6-4-1}{12}=\frac{2-1}{12}=\frac{1}{12}

Answer

112 \frac{1}{12}

Exercise #15

3511015= \frac{3}{5}-\frac{1}{10}-\frac{1}{5}=

Video Solution

Step-by-Step Solution

Let's try to find the least common denominator between 5 and 10

To find the least common denominator, we need to find a number that is divisible by both 5 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 2

We'll multiply the second fraction by 1

We'll multiply the third fraction by 2

3×25×21×110×11×25×2=610110210 \frac{3\times2}{5\times2}-\frac{1\times1}{10\times1}-\frac{1\times2}{5\times2}=\frac{6}{10}-\frac{1}{10}-\frac{2}{10}

Now let's subtract:

61210=5210=310 \frac{6-1-2}{10}=\frac{5-2}{10}=\frac{3}{10}

Answer

310 \frac{3}{10}

Exercise #16

325814= \frac{3}{2}-\frac{5}{8}-\frac{1}{4}=

Video Solution

Step-by-Step Solution

Let's try to find the least common denominator between 2 and 8 and 4

To find the least common denominator, we need to find a number that is divisible by 2, 8, and 4

In this case, the common denominator is 8

Now we'll multiply each fraction by the appropriate number to reach the denominator 8

We'll multiply the first fraction by 4

We'll multiply the second fraction by 1

We'll multiply the third fraction by 2

3×42×45×18×11×24×2=1285828 \frac{3\times4}{2\times4}-\frac{5\times1}{8\times1}-\frac{1\times2}{4\times2}=\frac{12}{8}-\frac{5}{8}-\frac{2}{8}

Now let's subtract:

12528=728=58 \frac{12-5-2}{8}=\frac{7-2}{8}=\frac{5}{8}

Answer

58 \frac{5}{8}

Exercise #17

4613112= \frac{4}{6}-\frac{1}{3}-\frac{1}{12}=

Video Solution

Step-by-Step Solution

Let's try to find the lowest common denominator between 6, 3, and 12

To find the lowest common denominator, we need to find a number that is divisible by 6, 3, and 12

In this case, the common denominator is 12

Now we'll multiply each fraction by the appropriate number to reach the denominator 12

We'll multiply the first fraction by 2

We'll multiply the second fraction by 4

We'll multiply the third fraction by 1

4×26×21×43×41×112×1=812412112 \frac{4\times2}{6\times2}-\frac{1\times4}{3\times4}-\frac{1\times1}{12\times1}=\frac{8}{12}-\frac{4}{12}-\frac{1}{12}

Now let's subtract:

84112=4112=312 \frac{8-4-1}{12}=\frac{4-1}{12}=\frac{3}{12}

Let's divide both numerator and denominator by 3 and we get:

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

Answer

14 \frac{1}{4}

Exercise #18

13+71525= \frac{1}{3}+\frac{7}{15}-\frac{2}{5}=

Video Solution

Step-by-Step Solution

Let's try to find the lowest common denominator between 3, 15, and 5

To find the lowest common denominator, we need to find a number that is divisible by 3, 15, and 5

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 5

We'll multiply the second fraction by 1

We'll multiply the third fraction by 3

1×53×5+7×115×12×35×3=515+715615 \frac{1\times5}{3\times5}+\frac{7\times1}{15\times1}-\frac{2\times3}{5\times3}=\frac{5}{15}+\frac{7}{15}-\frac{6}{15}

Now we'll add and then subtract:

5+7615=12615=615 \frac{5+7-6}{15}=\frac{12-6}{15}=\frac{6}{15}

We'll divide both numerator and denominator by 3 and get:

6:315:3=25 \frac{6:3}{15:3}=\frac{2}{5}

Answer

25 \frac{2}{5}

Exercise #19

10121326= \frac{10}{12}-\frac{1}{3}-\frac{2}{6}=

Video Solution

Step-by-Step Solution

Let's try to find the lowest common denominator between 6, 3, and 12

To find the lowest common denominator, we need to find a number that is divisible by 6, 3, and 12

In this case, the common denominator is 12

Now we'll multiply each fraction by the appropriate number to reach the denominator 12

We'll multiply the first fraction by 1

We'll multiply the second fraction by 4

We'll multiply the third fraction by 2

10×112×11×43×42×26×2=1012412412 \frac{10\times1}{12\times1}-\frac{1\times4}{3\times4}-\frac{2\times2}{6\times2}=\frac{10}{12}-\frac{4}{12}-\frac{4}{12}

Now let's subtract:

104412=6412=212 \frac{10-4-4}{12}=\frac{6-4}{12}=\frac{2}{12}

Let's divide both numerator and denominator by 2 and we get:

2:212:2=16 \frac{2:2}{12:2}=\frac{1}{6}

Answer

16 \frac{1}{6}