Odpowiedź :
a) p = 1/3 + 1/5 = 5/15 + 3/15 = 8/15
r = 1/3 - 1/5 = 5/15 - 3/15 = 2/15
s = 1/3 * 1/5 = 1/15
t = 1/3 : 1/5 = 1/3 * 5/1 = 1/3 * 5 = 5/3 = 1 2/3 = 1 10/15
s < r < p < t
b) p = 1/4 + 2/3 = 3/12 + 8/12 = 11/12 = 49,5/54
r = 2 5/6 - 1 1/9 = 2 45/54 - 1 6/54 = 1 39/54
s = 1 1/4 * 2/3 = 5/4 * 2/3 = 10/12 = 45/54
t = 1 1/4 : 2/3 = 5/4 * 3/2 = 15/8 = 1 7/8 = 1 47.25/54
s < p < r < t
c) p = 2 5/6 + 1 1/9 =2 45/54 + 1 6/54 = 3 51/54
r = 2 5/6 - 1 1/9 = 2 45/54 - 1 6/54 = 1 39/54
s = 2 5/6 * 1 1/9 = 17/6 * 10/9 = 170/54 = 3 8/54
t = 2 5/6 : 1 1/9 = 17/6 * 9/10 = 153/60 = 2 33/60
r < t < s < p
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