`4^8 · 8^4 = (2^2)^8 · (2^3)^4 = 2^16 · 2^12 = 2^28 `
`5^12 · 7 - 5^11 · 10 = 5^11 · 7 (5 - 3) = 5^11 · 7 · 2 = 5^11 · 14 `
`2^20 · 15+2^10 · 85 = 2^10 · 15(2^10 + 70)`
`27^16:9^10 = frac{(3^3)^16}{(3^2)^10} = frac{3^48}{3^20} = 3^28`
`125^3:25^4 = frac{(5^3)^3}{(5^2)^4} = frac{5^9}{5^8} = 5`
`24^4 : 3^4 - 32^12:16^12 = 24^4 : 3^4 - (2^5)^12 : (2^4)^12`
`= 8^4 - 2^12 = (2^3)^4 - 2^12`
`= 2^12 - 2^12 = 0`