2целых 2\5*(3 целых 2\5-1 целая 11\15)= 6 целых 3\8*1 целая 7\17-2 целых 3\8* 1 целая 1\4+2\5= 6 целых 3\7*3 целых 1\3: 1 целая 2\7= (7 целых 2\3- 5 целых 4\5): 2 целых 4\5=

2²/₅ × (3²/₅-1¹¹/₁₅) = ¹²/₅ × (¹⁷/₅-²⁶/₁₅)= 4
¹⁷/₅ - ²⁶/₁₅ = ¹⁷ˣ³/₁₅ - ²⁶/₁₅ = ⁵¹/₁₅ - ²⁶/₁₅ = ²⁵/₁₅ = ⁵/₃
¹²/₅ × ⁵/₃ = ¹²ˣ⁵/₅ₓ₃ = ¹²/₃ = 4

6³/₈ × 1⁷/₁₇-2³/₈ × 1¹/₄+²/₅= 6⁶⁹/₁₆₀
6³/₈ × 1⁷/₁₇ = ⁵¹/₈ × ²⁴/₁₇ = ⁵¹ˣ²⁴/₈ₓ₁₇ = ³ˣ³/₁ = ⁹/₁ = 9
2³/₈  × 1¹/₄ = ¹⁹/₈  × ⁵/₄ = ¹⁹ˣ⁵/₈ₓ₄ = ⁹⁵/₃₂ = 2³¹/₃₂
9 - 2³¹/₃₂ = 8³²/₃₂ - 2³¹/₃₂ = 6¹/₃₂
6¹/₃₂ + ²/₅ = ¹⁹³/₃₂ + ²/₅ = ¹⁹³ˣ⁵/₁₆₀ + ²ˣ³²/₁₆₀=¹⁹³ˣ⁵/₁₆₀ + ²ˣ³²/₁₆₀=⁹⁶⁵/₁₆₀ + ⁶⁴/₁₆₀=
⁹⁶⁵⁺⁶⁴/₁₆₀ = ¹⁰²⁹/₁₆₀ = 6⁶⁹/₁₆₀

6³/₇ × 3¹/₃ : 1²/₇= 16²/₃
6³/₇ × 3¹/₃ =  ⁴⁵/₇ × ¹⁰/₃ = ⁴⁵ˣ¹⁰/₇ₓ₃ = ¹⁵ˣ¹⁰/₇= ¹⁵⁰/₇ 
¹⁵⁰/₇ : 1²/₇ = ¹⁵⁰/₇ : ⁹/₇ = ¹⁵⁰/₇ × ⁷/₉ = ¹⁵⁰ˣ⁷/₇ₓ₉ = ¹⁵⁰/₉ = ⁵⁰/₃ = 16²/₃

(7²/₃- 5⁴/₅) : 2⁴/₅= ²/₃
7²/₃- 5⁴/₅ = ²³/₃ - ²⁹/₅ = ²³ˣ⁵/₁₅ - ²⁹ˣ³/₁₅ = ¹¹⁵/₁₅ - ⁸⁷/₁₅ = ¹¹⁵⁻⁸⁷/₁₅ = ²⁸/₁₅ 
²⁸/₁₅ : 2⁴/₅ = ²⁸/₁₅ : ¹⁴/₅ =  ²⁸/₁₅ × ⁵/₁₄ = ²⁸ˣ⁵/₁₅ₓ₁₄ = ²/₃

1) 2 2/5*(3 2/5 - 1 11/15) =4
3 2/5 - 1 11/15) = 17/5 - 26/15 = 17*3/5*3 - 26/15 = 51-26/15 =25/15=5/3= 1 2/3
2 2/5 * 1 2/3 = 12/5*5/3 = 12*5/5*3 = 60/15 = 4

3) 6 3\7*3 1\3: 1 2\7= 16 2/3
6 3/7*3 1/3 = 45/7*10/3 = 45*10/7*3 = 450/21 = 150/7 = 21 3/7
21 3/7 : 1 2/7 = 150/7 : 9/7 = 150/7 * 7/9 = 150*7/7*9 = 1050/63 = 50/3 = 16 2/3

4) (7 2\3- 5  4\5):2 4\5= 2/3
7 2/3 - 5 4/5 = 23/3 - 29/5 = 23*5/3*5 - 29*3/5*3 = 115/15 - 87/15 = 115-87/15 =28/15=1 13/15
1 13/15 : 2 4/5 = 28/15 : 14/5 = 28/15*5/14 = 28*5/15*14 = 140/210 = 2/3