1). 8*3125-5186=25000-5186=19814. 2). 100000*10:1000=1000 3).872:8*7=763
8а+4а=12а
14х-9х=5х
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1) 3 1/4 - 3 5/12 = 1/4 - 5/12 = 3/12 - 5/12 = -2/12 = - 1/6.
1254*31+25250=64124
12428:26+25108=25586
855:285+11*265=28218
25899+90052-680=115271