Odpowiedź:
Musisz sprowadzić do wspólnego mianownika
1/2 + 3/4 = 2/4 + 3/4 = 5/4 = 1 ¼
1/3 + 7/9 = 3/9 + 7/9 = 10/9 = 1 1/9
5/6 + 1 1/4 = 5/6 + 5/4 = 20/24 + 30/24 = 50/24 = 2 2/24
2 1/4 + 1 2/3 = 9/4 + 5/3 = 27/12 + 20/12 = 47/12 = 3 11/12
1 ⅚ + 7/9 = 11/6 + 7/9 = 33/18 + 17/18 = 50/18 = 2 14/18 = 2 7/9
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½ - ¼ = 2/4 - ¼ = ¼
⅚ - ⅔ = ⅚ - 4/6 = ⅙
¾ - ⅜ = 6/8 - ⅜ = 3/8
3 5/9 - ⅙ = 32/9 - ⅙ = 64/18 - 3/18 = 61/18 = 3 7/18
1 ¾ - ⅚ = 7/4 - ⅚ = 21/12 - 10/12 = 11/12
2 1/9 - 1⅚ = 19/9 - 11/6 = 38/18 - 33/18 = 5/18
