3,6*1,7=3,4*х
х=3,6*1,7:3,4
х= 1,8 дм - ширина второго
-5а+34а+а = 120
30а = 120
а = 120:30
а = 4
х(15*6:9*11)+х(90:5)*8=320
1)x/4=11/36+4/9
x/4=11/36+16/36
x/4=27/36=3/4
x=3/4×4
x=3
2)x/75=11/25+1/15
x/75=33/75+5/75
x/75=38/75
x=38/75×75
x=38
3)x/48=5/16+1/3
x/48=15/48+16/48
x/48=31/48
x=31/48×48
x=31
0, 045678
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