Greetings from Brasil...
Here's our problem:
[tex]\large{\frac{12^{3}}{12^{7}}}[/tex]
From potentiation properties:
Mᵃ ÷ Mᵇ = Mᵃ⁻ᵇ
division of power of the same base: I repeat the base and subtract the exponents
So, in our problem
[tex]\large{\frac{12^{3}}{12^{7}}}[/tex] = 12³ ÷ 12⁷
12³ ÷ 12⁴ = 12³⁻⁷
12⁻⁴
We also know about another property: P⁻ⁿ = (1/Pⁿ) so
12⁻⁴ = (1/12⁴)
