(73,6 - 72 5/9) : 6 4/15 + 7/13 · (20 2/3 - 19 3/7) = 5/6
1) 73,6 - 72 5/9 = 73 3/5 - 72 5/9 = 73 27/45 - 72 25/45 = 1 2/45
2) 1 2/45 : 6 4/15 = 47/45 : 94/15 = 47/45 · 15/94 = (1·3)/(9·2) = 3/18 = 1/6
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3) 20 2/3 - 19 3/7 = 20 14/21 - 19 9/21 = 1 5/21
4) 7/13 · 1 5/21 = 7/13 · 26/21 = (1·2)/(1·3) = 2/3
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5) 1/6 + 2/3 = 1/6 + 4/6 = 5/6
(x-y+19)+(y-x-10)=x-y+19+y-x-10=9
Ле+дни=ледни
ледни-ени=лд
лд+<span>есн=лд</span>есн
лд<span>есн-д=лесн</span>
<span>лесн+</span><span>ик</span>=лесник
13×9=117 (произведение это × )