Question

15a2bm-6a2bn; 30ab2m-12ab2n

Answer 1

$15 a^{2}bm -6 a^{2} bn = 3 a^{2}b(5m-2n)$

$30a b^{2} m -12a b^{2} n = 6a b^{2} (5m-2n)$