Б) 3⁴/₅+1¹/₆ = ¹⁹/₅+⁷/₆ = ¹⁹ˣ⁶/₃₀+⁷ˣ⁵/₃₀ = ¹¹⁴/₃₀+³⁵/₃₀ = ¹¹⁴⁺³⁵/₃₀ = ¹⁴⁹/₃₀ = 4²⁹/₃₀
в) 4¹⁰/₂₇-⁵/₁₈ = ¹¹⁸/₂₇-⁵/₁₈ = ¹¹⁸ˣ²/₅₄-⁵ˣ³/₅₄ = ²³⁶/₅₄-¹⁵/₅₄ = ²³⁶⁻¹⁵/₅₄ = ²²¹/₅₄ = 4⁵/₅₄
г) 5⁵/₉-2¹/₃ = ⁵⁰/₉-⁷/₃ = ⁵⁰/₉-²¹/₉ = ⁵⁰⁻²¹/₉ = ²⁹/₉ = 3²/₃
или
5 5/9-21/3 = 5⁵/₉-²¹/₃ = ⁵⁰/₉-²¹/₃ = ⁵⁰/₉-²¹ˣ³/₉ = ⁵⁰/₉-⁶³/₉ = ⁵⁰⁻⁶³/₉ = - ¹³/₉ = - 1⁴/₉