1)23 7 = 24 6 4 =6 24х2=48 6х2=12 48+12=60
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2)15 45 = 15 23 07 =23 15х2=30 23х2=46 30+46=76
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3)19 08 = 19 8 832 = 9 19х2=28 9х2=18 28+18=46
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4)13 78 = 14 12 087 = 12 14х2=28 12х2=24 28 + 24 = 52