3)
=1/3 * (3/5) = 1/5
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7)
1) 45:3 6/13 = 45 * 13/45 = 13
2) 13,6 - 13 = 0,6
3) 0,6 + 1 3/8 = 3/5 + 1 3/8 = 24/40 + 1 15/40 = 1 39/40
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9)
=12y-4y+3y-1 = 11y-1 = 11 * 3/11 - 1 = 3 - 1 =2
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