Find the Indicated Quotients $\left( \frac { 18 x ^ { - 4 } y ^ { - 4 } } { 9 x ^ { 7 } y ^ { 7 } } \right) ^ { - 1 }$

Short Answer

Find the indicated quotients. Express final results using positive integral exponents only. $\left( \frac { 18 x ^ { - 4 } y ^ { - 4 } } { 9 x ^ { 7 } y ^ { 7 } } \right) ^ { - 1 }$ Please enter your answer as a fraction.