Question

what will be the least number which when doubled will be exactly divisible by 12,18,21, and 30? (please give answer I take the mark brainlist)​

Answer 1

Let the number be x

2x = L.C.M of 12, 18, 21 and 30

12 = 2  × 2 ×  3  

18 = 2 × 3 × 3

21 = 3 × 7  

30 = 2 × 3 × 5

LCM = 2 × 2 × 3 × 3 × 5 × 7

        = 1260

2x = 1260

x = 1260/2

x = 630