<span>1)2,3а+(-3,56а)+7,8а =2,3а-3,56а+7,8а=7,54а</span>
2)-69,7с+34,83с+(-26,18с)=-69,7с+34,83с-26,18с=-61,05с
<span>3)-14 1/2 в+ 8 4/15в (-9 1/6 в )= -14,1/2в+8,4/15в-9,1/6в= -15,2/3в</span>
<span><span>4)5,36д+(-9,13д)+(-5,46д)</span>=5,36д-9,13д-5,46д= -9,23д
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