12=2•2•3
18=2•3•3
20=2•2•5
НОК(12;18;20)=2•2•3•5=60
40 - 100%
40/100 =0,4
0,4 • 45 = 10 девочек
39/81 = 13/27
(13 : 27) * 27 = 13
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90/373
(90 : 373) * 373 = 90
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3232/9405
(3232 : 9405) * 9405 = 3232
14,040÷18+6,110÷13=1,250
6,576÷12−7,047÷783=539
80,302−64×71=75,758
7,069+595×62,300×270=10,008,502,069
400×207=82,800