Final answer:
To subtract 7¹/⁹ - 2⁴/²⁷, rewrite both fractions with a common denominator of 27. Then subtract the numerators and simplify.
Step-by-step explanation:
To subtract 7¹/⁹ - 2⁴/²⁷, we need to have a common denominator. The least common multiple of 9 and 27 is 27. So we can rewrite 7¹/⁹ as (7 * 3)/27, and 2⁴/²⁷ as (2⁴ * 3⁴)/27. Now we can subtract the fractions: ((7 * 3) - (2⁴ * 3⁴))/27. Simplifying the numerator gives us (21 - 16 * 81)/27, which further simplifies to (21 - 1296)/27 = -1275/27.