Name
Grade
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Date
Questions20
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1

Find the LCM of 16, 24 and 36

2

Find the LCM of 36, 54 and 72

3

Find the LCM of 9, 12 and 16

4

Find the LCM of 6, 8 and 10

5

Find the LCM of 8, 12 and 15

6

Find the LCM of 9, 10 and 15

7

Find the LCM of 8, 9 and 12

8

Find the LCM of 5, 6 and 10

9

Find the LCM of 5, 8 and 10

10

Find the LCM of 30, 36 and 45

11

Find the LCM of 8, 10 and 15

12

Find the LCM of 18, 27 and 36

13

Find the LCM of 9, 15 and 18

14

Find the LCM of 24, 36 and 48

15

Find the LCM of 30, 40 and 50

16

Find the LCM of 10, 20 and 30

17

Find the LCM of 7, 9 and 21

18

Find the LCM of 28, 42 and 56

19

Find the LCM of 16, 20 and 30

20

Find the LCM of 12, 24 and 36

Answers Key

1

Find the LCM of 16, 24 and 36

144 is the LCM of 16, 24 and 36

Factors of 16

2 | 16 |

2 | 8 |

2 | 4 |

2 | 2 |

1 |

Factors of 24

2 | 24 |

2 | 12 |

2 | 6 |

3 | 3 |

1 |

Factors of 36

2 | 36 |

2 | 18 |

3 | 9 |

3 | 3 |

1 |

Factors of 16 = 2 x 2 x 2 x 2

Factors of 24 = 2 x 2 x 2 x 3

Factors of 36 = 2 x 2 x 3 x 3

Multiply all the common and uncommon factors of 16, 24 and 36.

2 x 2 x 2 x 2 x 3 x 3 = 144

LCM(16, 24, 36) = 144

2

Find the LCM of 36, 54 and 72

216 is the LCM of 36, 54 and 72

Factors of 36

2 | 36 |

2 | 18 |

3 | 9 |

3 | 3 |

1 |

Factors of 54

2 | 54 |

3 | 27 |

3 | 9 |

3 | 3 |

1 |

Factors of 72

2 | 72 |

2 | 36 |

2 | 18 |

3 | 9 |

3 | 3 |

1 |

Factors of 36 = 2 x 2 x 3 x 3

Factors of 54 = 2 x 3 x 3 x 3

Factors of 72 = 2 x 2 x 2 x 3 x 3

Multiply all the common and uncommon factors of 36, 54 and 72.

2 x 2 x 2 x 3 x 3 x 3 = 216

LCM(36, 54, 72) = 216

3

Find the LCM of 9, 12 and 16

144 is the LCM of 9, 12 and 16

Factors of 9

3 | 9 |

3 | 3 |

1 |

Factors of 12

2 | 12 |

2 | 6 |

3 | 3 |

1 |

Factors of 16

2 | 16 |

2 | 8 |

2 | 4 |

2 | 2 |

1 |

Factors of 9 = 3 x 3

Factors of 12 = 2 x 2 x 3

Factors of 16 = 2 x 2 x 2 x 2

Multiply all the common and uncommon factors of 9, 12 and 16.

2 x 2 x 2 x 2 x 3 x 3 = 144

LCM(9, 12, 16) = 144

4

Find the LCM of 6, 8 and 10

120 is the LCM of 6, 8 and 10

Factors of 6

2 | 6 |

3 | 3 |

1 |

Factors of 8

2 | 8 |

2 | 4 |

2 | 2 |

1 |

Factors of 10

2 | 10 |

5 | 5 |

1 |

Factors of 6 = 2 x 3

Factors of 8 = 2 x 2 x 2

Factors of 10 = 2 x 5

Multiply all the common and uncommon factors of 6, 8 and 10.

2 x 2 x 2 x 3 x 5 = 120

LCM(6, 8, 10) = 120

5

Find the LCM of 8, 12 and 15

120 is the LCM of 8, 12 and 15

Factors of 8

2 | 8 |

2 | 4 |

2 | 2 |

1 |

Factors of 12

2 | 12 |

2 | 6 |

3 | 3 |

1 |

Factors of 15

3 | 15 |

5 | 5 |

1 |

Factors of 8 = 2 x 2 x 2

Factors of 12 = 2 x 2 x 3

Factors of 15 = 3 x 5

Multiply all the common and uncommon factors of 8, 12 and 15.

2 x 2 x 2 x 3 x 5 = 120

LCM(8, 12, 15) = 120

6

Find the LCM of 9, 10 and 15

90 is the LCM of 9, 10 and 15

Factors of 9

3 | 9 |

3 | 3 |

1 |

Factors of 10

2 | 10 |

5 | 5 |

1 |

Factors of 15

3 | 15 |

5 | 5 |

1 |

Factors of 9 = 3 x 3

Factors of 10 = 2 x 5

Factors of 15 = 3 x 5

Multiply all the common and uncommon factors of 9, 10 and 15.

2 x 3 x 3 x 5 = 90

LCM(9, 10, 15) = 90

7

Find the LCM of 8, 9 and 12

72 is the LCM of 8, 9 and 12

Factors of 8

2 | 8 |

2 | 4 |

2 | 2 |

1 |

Factors of 9

3 | 9 |

3 | 3 |

1 |

Factors of 12

2 | 12 |

2 | 6 |

3 | 3 |

1 |

Factors of 8 = 2 x 2 x 2

Factors of 9 = 3 x 3

Factors of 12 = 2 x 2 x 3

Multiply all the common and uncommon factors of 8, 9 and 12.

2 x 2 x 2 x 3 x 3 = 72

LCM(8, 9, 12) = 72

8

Find the LCM of 5, 6 and 10

30 is the LCM of 5, 6 and 10

Factors of 5

5 | 5 |

1 |

Factors of 6

2 | 6 |

3 | 3 |

1 |

Factors of 10

2 | 10 |

5 | 5 |

1 |

Factors of 5 = 5

Factors of 6 = 2 x 3

Factors of 10 = 2 x 5

Multiply all the common and uncommon factors of 5, 6 and 10.

2 x 3 x 5 = 30

LCM(5, 6, 10) = 30

9

Find the LCM of 5, 8 and 10

40 is the LCM of 5, 8 and 10

Factors of 5

5 | 5 |

1 |

Factors of 8

2 | 8 |

2 | 4 |

2 | 2 |

1 |

Factors of 10

2 | 10 |

5 | 5 |

1 |

Factors of 5 = 5

Factors of 8 = 2 x 2 x 2

Factors of 10 = 2 x 5

Multiply all the common and uncommon factors of 5, 8 and 10.

2 x 2 x 2 x 5 = 40

LCM(5, 8, 10) = 40

10

Find the LCM of 30, 36 and 45

180 is the LCM of 30, 36 and 45

Factors of 30

2 | 30 |

3 | 15 |

5 | 5 |

1 |

Factors of 36

2 | 36 |

2 | 18 |

3 | 9 |

3 | 3 |

1 |

Factors of 45

3 | 45 |

3 | 15 |

5 | 5 |

1 |

Factors of 30 = 2 x 3 x 5

Factors of 36 = 2 x 2 x 3 x 3

Factors of 45 = 3 x 3 x 5

Multiply all the common and uncommon factors of 30, 36 and 45.

2 x 2 x 3 x 3 x 5 = 180

LCM(30, 36, 45) = 180

11

Find the LCM of 8, 10 and 15

120 is the LCM of 8, 10 and 15

Factors of 8

2 | 8 |

2 | 4 |

2 | 2 |

1 |

Factors of 10

2 | 10 |

5 | 5 |

1 |

Factors of 15

3 | 15 |

5 | 5 |

1 |

Factors of 8 = 2 x 2 x 2

Factors of 10 = 2 x 5

Factors of 15 = 3 x 5

Multiply all the common and uncommon factors of 8, 10 and 15.

2 x 2 x 2 x 3 x 5 = 120

LCM(8, 10, 15) = 120

12

Find the LCM of 18, 27 and 36

108 is the LCM of 18, 27 and 36

Factors of 18

2 | 18 |

3 | 9 |

3 | 3 |

1 |

Factors of 27

3 | 27 |

3 | 9 |

3 | 3 |

1 |

Factors of 36

2 | 36 |

2 | 18 |

3 | 9 |

3 | 3 |

1 |

Factors of 18 = 2 x 3 x 3

Factors of 27 = 3 x 3 x 3

Factors of 36 = 2 x 2 x 3 x 3

Multiply all the common and uncommon factors of 18, 27 and 36.

2 x 2 x 3 x 3 x 3 = 108

LCM(18, 27, 36) = 108

13

Find the LCM of 9, 15 and 18

90 is the LCM of 9, 15 and 18

Factors of 9

3 | 9 |

3 | 3 |

1 |

Factors of 15

3 | 15 |

5 | 5 |

1 |

Factors of 18

2 | 18 |

3 | 9 |

3 | 3 |

1 |

Factors of 9 = 3 x 3

Factors of 15 = 3 x 5

Factors of 18 = 2 x 3 x 3

Multiply all the common and uncommon factors of 9, 15 and 18.

2 x 3 x 3 x 5 = 90

LCM(9, 15, 18) = 90

14

Find the LCM of 24, 36 and 48

144 is the LCM of 24, 36 and 48

Factors of 24

2 | 24 |

2 | 12 |

2 | 6 |

3 | 3 |

1 |

Factors of 36

2 | 36 |

2 | 18 |

3 | 9 |

3 | 3 |

1 |

Factors of 48

2 | 48 |

2 | 24 |

2 | 12 |

2 | 6 |

3 | 3 |

1 |

Factors of 24 = 2 x 2 x 2 x 3

Factors of 36 = 2 x 2 x 3 x 3

Factors of 48 = 2 x 2 x 2 x 2 x 3

Multiply all the common and uncommon factors of 24, 36 and 48.

2 x 2 x 2 x 2 x 3 x 3 = 144

LCM(24, 36, 48) = 144

15

Find the LCM of 30, 40 and 50

600 is the LCM of 30, 40 and 50

Factors of 30

2 | 30 |

3 | 15 |

5 | 5 |

1 |

Factors of 40

2 | 40 |

2 | 20 |

2 | 10 |

5 | 5 |

1 |

Factors of 50

2 | 50 |

5 | 25 |

5 | 5 |

1 |

Factors of 30 = 2 x 3 x 5

Factors of 40 = 2 x 2 x 2 x 5

Factors of 50 = 2 x 5 x 5

Multiply all the common and uncommon factors of 30, 40 and 50.

2 x 2 x 2 x 3 x 5 x 5 = 600

LCM(30, 40, 50) = 600

16

Find the LCM of 10, 20 and 30

60 is the LCM of 10, 20 and 30

Factors of 10

2 | 10 |

5 | 5 |

1 |

Factors of 20

2 | 20 |

2 | 10 |

5 | 5 |

1 |

Factors of 30

2 | 30 |

3 | 15 |

5 | 5 |

1 |

Factors of 10 = 2 x 5

Factors of 20 = 2 x 2 x 5

Factors of 30 = 2 x 3 x 5

Multiply all the common and uncommon factors of 10, 20 and 30.

2 x 2 x 3 x 5 = 60

LCM(10, 20, 30) = 60

17

Find the LCM of 7, 9 and 21

63 is the LCM of 7, 9 and 21

Factors of 7

7 | 7 |

1 |

Factors of 9

3 | 9 |

3 | 3 |

1 |

Factors of 21

3 | 21 |

7 | 7 |

1 |

Factors of 7 = 7

Factors of 9 = 3 x 3

Factors of 21 = 3 x 7

Multiply all the common and uncommon factors of 7, 9 and 21.

3 x 3 x 7 = 63

LCM(7, 9, 21) = 63

18

Find the LCM of 28, 42 and 56

168 is the LCM of 28, 42 and 56

Factors of 28

2 | 28 |

2 | 14 |

7 | 7 |

1 |

Factors of 42

2 | 42 |

3 | 21 |

7 | 7 |

1 |

Factors of 56

2 | 56 |

2 | 28 |

2 | 14 |

7 | 7 |

1 |

Factors of 28 = 2 x 2 x 7

Factors of 42 = 2 x 3 x 7

Factors of 56 = 2 x 2 x 2 x 7

Multiply all the common and uncommon factors of 28, 42 and 56.

2 x 2 x 2 x 3 x 7 = 168

LCM(28, 42, 56) = 168

19

Find the LCM of 16, 20 and 30

240 is the LCM of 16, 20 and 30

Factors of 16

2 | 16 |

2 | 8 |

2 | 4 |

2 | 2 |

1 |

Factors of 20

2 | 20 |

2 | 10 |

5 | 5 |

1 |

Factors of 30

2 | 30 |

3 | 15 |

5 | 5 |

1 |

Factors of 16 = 2 x 2 x 2 x 2

Factors of 20 = 2 x 2 x 5

Factors of 30 = 2 x 3 x 5

Multiply all the common and uncommon factors of 16, 20 and 30.

2 x 2 x 2 x 2 x 3 x 5 = 240

LCM(16, 20, 30) = 240

20

Find the LCM of 12, 24 and 36

72 is the LCM of 12, 24 and 36

Factors of 12

2 | 12 |

2 | 6 |

3 | 3 |

1 |

Factors of 24

2 | 24 |

2 | 12 |

2 | 6 |

3 | 3 |

1 |

Factors of 36

2 | 36 |

2 | 18 |

3 | 9 |

3 | 3 |

1 |

Factors of 12 = 2 x 2 x 3

Factors of 24 = 2 x 2 x 2 x 3

Factors of 36 = 2 x 2 x 3 x 3

Multiply all the common and uncommon factors of 12, 24 and 36.

2 x 2 x 2 x 3 x 3 = 72

LCM(12, 24, 36) = 72