Question

find the LCM of 18, 21 ,28 and 30​

Answer 1

Answer:

The LCM is 1260 .

Step-by-step explanation:

LCM= 1260

Answer 2

Answer:

The LCM of 18, 21 ,28 and 30 is

1,260.

Step-by-step explanation:

★ 18 :

2 | 18

3 | 9

3 | 3

$\:\:$ | 1

18 = 2 × 3 × 3

___________________________

★ 21 :

3 | 21

7 | 7

$\:\:$ | 1

21 = 3 × 7

___________________________

★ 28 :

2 | 28

2 | 14

7 | 7

$\:\:$ | 1

28 = 2 × 2 × 7

___________________________

★ 30 :

2 | 30

3 | 15

5 | 5

$\:\:$ | 1

30 = 2 × 3 × 5

___________________________

• 18 = 2 × 3 × 3
• 21 = 3 × 7
• 28 = 2 × 2 × 7
• 30 = 2 × 3 × 5

★ LCM = 2 × 3 × 3 × 7 × 2 × 5

= 1,260

LCM = 1,260

Therefore, the LCM of 18, 21 ,28 and 30 is 1,260.