1) 5xn+245=845 (=)5xn=845-245(=)5xn=600(=)xn=600:5(=)xn=60(=)xn=60.
2)54:n+67x5=344(=)54:n+335=334(=)54:n=335-334(=)54:n=1(=)n=54x1(=)n=54
3) n:3x8=616(=)n:3=616:8(=)n:3=77(=)n=77x3(=)n=231
4)894-n:4=833(=)n:4=833+894(=)n:4=1787(=)n:4=1787:4(=)n=446
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