28)
1) 4,2:0,1 =42:1 =42 ;
2) 3+42 =45 ;
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3) 1:0,3 =10/3 ;
4) 10/3 - 2 1/3 =3 1/3 -2 1/3 =1 ;* * * 10/3 -7/3 =(10-7)/3 =3/3 =1 * * *
5) 1*0,3125 =0,3125 ;
6) 45:0,3125 =144;
x*3,6/100 =144 ;
7) 144*100/3,6 = 144000/36 =4000.
ответ: 4000.
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НОД(38;b) =2 ; НОК(38 ;b ) =1216 .
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b -?
НОД(a;b) * НОК(a ;b) =a*b.
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2*1216 =38*b;
b=2*1216/38 =1216/19 =64.
ответ: 64.