Răspuns:
Explicație pas cu pas:
7a)
7/2 + x = 49/4
x = 49/4 - 7/2 = 49/4 - 14/4 = 35/4 = 8 3/4 (8 intregi si 3/4)
b)
9/2 - x = 7/3
x = 9/2 - 7/3 = 27/6 - 14/6 = 13/6 = 2 1/6
5x/2 = 19/4
20x = 38
x = 38/20 = 19/10 = 1 9/10 (sau 1,9)
d) nu se vede complet
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10.
11/12 - 7/36 = 33/36 - 7/36 = 26/36
5/6 - 26/36 = 30/36 - 26/36 = 4/36 = 1/9
5/51 * 1/9 : 25/72 = 5/51*1/9*72/25 = 8/255
