450x^2 y^5 3000x^4 y^3
look at what's common on each exponent first.
for x it would be x^2 and y would be y^1
then divide the x by 150 which is common for both.
150x^2
then for the y you can't do anything else
so your answer is 150x^2 y^1
*NOTE: anything to the first power isn't visible so your answer is 150x^2 y
Read this slow and go step by step. Hope you understand and hope this help answer your question. :)