Answer:
90, see below :)
Explanation:
Hello!
The best way to find LCM (lowest common multiple) is to first list the prime factorization. Then you multiply the ones that overlap once and then the different ones.
30: 2 * 3 * 5
45: 3 * 3 * 5
We can see 3 and 5 overlaps so we only multiply it once:
2 * 3
And then both times 3 and 5
6 * 5 * 3 = 90