Сравните НОК(a;b)•НОД(a;b) иa•b a21;27b12;15;a68;102;b17;34

1) 5/24+7/60 = 25/120 + 14/120 = 39/120 = 13/40
2) 11/21-3/35 = 55/105 - 9/105 = 46/105
3) 5/42+10/63 = 15/126 + 20/126 = 35/126 = 5/18
4) 19/60-8/45 = 57/180 - 32/180 = 25/180 = 5/36
5) 5/18+9/24-7/12 = 20/72 + 27/72 - 42/72 = 5/72
6) 3/20-2/25+1/30 = 45/300 - 24/300 + 10/300 = 31/300

47 км 390 м = 47 390 м
15 км 860 м = 15 860 м

47 390 +15 860 = 63 250 м= 63 км 250 м

Равенство
48часов=2суткам
не равенство
48часов>2сутка

<span>в) (23,82+54,58)*(1,202+0,698)-2,1*(3,53-1,89)=145.52
1)</span>23,82+54,58=78,40
2)1,202+0,698=1.9
3)3,53-1,89=1,64
4)78.40*1.9=148.96
5)2.1*1.64=3.44
6)148.96-3.44=145.52

г)<span>316 219-(27 090:43+16 422:119)=315.451
1)27090:43=630
2)</span>16 422:119=138
3)630+138=768
4)316.219-768=315.451

518/360 = 1 79/180
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