$\frac{ 10{u}^{-1} \times 1 }{ 8{u}^{-4}{v}^{3} \times 5{v}^{2} }$
Cancel out the common factor $5$$\frac{ 2{u}^{-1} \times 1 }{ 8{u}^{-4}{v}^{3} \times {v}^{2} }$
Simplify the expression$\frac{ 2{u}^{3} \times 1 }{ 8{v}^{3} \times {v}^{2} }$
Any expression multiplied by $1$ remains the same$\frac{ 2{u}^{3} }{ 8{v}^{3} \times {v}^{2} }$
Cancel out the common factor $2$$\frac{ {u}^{3} }{ 4{v}^{3} \times {v}^{2} }$
Calculate the product$\frac{ {u}^{3} }{ 4{v}^{5} }$