2,1/5,1* 5 2/3-2,6/4,5:3 7/15= 2¹/₃
2,1 : 5,1 = ²¹/₁₀ : ⁵¹/₁₀ = ²¹/₁₀ × ¹⁰/₅₁ = ²¹ˣ¹⁰/₁₀ₓ₅₁ = ²¹/₅₁ = ⁷/₁₇
⁷/₁₇× 5²/₃ = ⁷/₁₇× ¹⁷/₃ = ⁷ˣ¹⁷/₁₇ₓ₃ = ⁷/₃
2,6 : 4,5 = ²⁶/₁₀ : ⁴⁵/₁₀ = ²⁶/₁₀ × ¹⁰/₄₅ = ²⁶ˣ¹⁰/₁₀ₓ₄₅ = ²⁶/₄₅
²⁶/₄₅ : 3⁷/₁₅ = ²⁶/₄₅ : ⁵²/₁₅ = ²⁶/₄₅ × ¹⁵/₅₂ = ²⁶ˣ¹⁵/₄₅ₓ₅₂ = ¹⁵/₄₅ₓ₂ = ¹/₃ₓ₂ = ¹/₆
⁷/₃ - ¹/₆ = ⁷ˣ²/₆ - ¹/₆ = ¹⁴/₆ = 2²/₆ = 2¹/₃
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10,26:3,8+1,4*12= 19,5
10,26:3,8 = 2,7
1,4 × 12 = 16,8
2,7 + 16,8 = 19,5