12 * 1 = 12 \(\leftarrow\) not a multiple of 5
12 * 2 = 24 \(\leftarrow\) not a multiple of 5
12 * 3 = 36 \(\leftarrow\) not a multiple of 5
12 * 4 = 48 \(\leftarrow\) not a multiple of 5
12 * 5 = 60 \(\leftarrow\) this is a multiple of 5
So...the least common multiple of 5 and 12 is 60