Răspuns:
Explicație pas cu pas:
a/b = 1,25 = 125/100 = 5/4
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a/b : 7/8 =5/4 : 7/8 = 5/4*8/7 = 10/7
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a/b : (-5) = 5/4 : (-5) = 5/4*(-1/5) = -1/4
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(-5*a) : b/2
a = 5b/4
-5*5b/4 : b/2 = -25b/4 : b/2 = -25b/4*2/b = -25/2
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a/5 : (-b/4) = [(5b/4)/5] : (-b/4) = b/4 : (-b/4) = -1