well, you already know how to convert from mixed to improper, so let's simply do the multiplication, as it's very straightforward.
[tex]\bf 4\frac{2}{7}\cdot 2\frac{1}{5}\implies \cfrac{30}{7}\cdot \cfrac{11}{5}\implies \cfrac{30}{5}\cdot \cfrac{11}{7}\implies 6\cdot \cfrac{11}{7}\implies \cfrac{66}{7}\implies 9\frac{3}{7}[/tex]