Can someone please help me on this problem? I’m don’t understand it...

Answer: [tex]\bold{\dfrac{7w^2y^3}{32}}[/tex]
Step-by-step explanation:
[tex]\dfrac{3w^9y^4}{8w^5}\cdot \dfrac{7y^4}{12w^2y^5}\\\\\\\text{Multiply across. ADD exponents when like bases are being multiplied}\\=\dfrac{21w^9y^8}{96w^7y^5}\\\\\\\text{Cancel out common factors. SUBTRACT exponents when dividing}\\=\dfrac{7w^2y^3}{32}[/tex]