2,4+3/5 -х=1 1/15 х+1,36
2 2/5 +3/5 -х=1 1/15 х +1,36
3-х=1 1/15 х+1,36
-х-1 1/15 х=1,36-3
- 2 1/15 х = - 1,64
х=1 16/25:2 1/15=41/25*15/31
х=<span>=41/155</span>
(16000+9*(900-50х)*4)/50-80*6=20
((16000+(8100-450х)*4)/50-480=20
(16000+32400-1800х)/50-480=20
16000/50+32400/50-1800х/50-480=20
320+648-36х-480=20
-36х=20-320-648+480
-36х=-468
х=468*36
х=13
90
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