Ответ:
х - гречка, значит
х=4*64000000=256000000(кг)
1) s/u
2) s-20
3) u-12
4) (s-20) : (u-12)
5) s/u - (s-20):(u-12)
6) s/u + (s-20):(u-12)
7) s+s-20 = 2s-20
8) (2s-20):(s/u+(s-20):(u-12))
<span>3х+у=4
y = 4 - 3x
5х+у=10
5x +(4-3x) =10
2x = 6
x = 3
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