Answer:
[tex]\frac{1}{343}[/tex]
Step-by-step explanation:
Using the rule of exponents
[tex]a^{-m}[/tex] ⇔ [tex]\frac{1}{a^{m} }[/tex] , then
[tex]7^{-3}[/tex]
= [tex]\frac{1}{7^{3} }[/tex] = [tex]\frac{1}{343}[/tex]
