LCM and HCF Practice Test 1

2 × 3 × 3 × 5 = 90
Hence, LCM of 6, 9, 15 and 18 = 90
Let required number be 90k + 4, which is multiple of 7.
The least value of k = 4, then 90k + 4 = 90 × 4 + 4 = 364 which is a multiple of 7.