Răspuns:
Explicație pas cu pas:
9/5 : (3/4*8/21 + 1) - 4/9 = 9/5 : (2/7 + 1) - 4/9 = 9/5 : 9/7 - 4/9 = 9/5*7/9 - 4/9 = 7/5 - 4/9 = 63/45 - 20/45 = 43/45
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[(1/3 + 2/21) : (1/18 + 1/14) - 5/2] *8
[(7/21 + 2/21) : (7/126 + 9/126)] *8
(9/21) : (16/126) *8
9/21 * 126/16 *8 = 27
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(1/12 + 1/24 - 1/36) : (1/4 + 3/5) *17/7
(6/72 + 3/72 - 2/72) : (5/20 + 12/20) * 17/7
7/72 : 17/20 * 17/7
7/72 * 20/17 * 17/7 = 5/18
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al 4-lea exercitiu nu se vede vine
