\(\frac{\left(X-1,75\right):0,01}{\left(1-0,75\right)x80}=41,25\)
\(\frac{\left(X-1,75\right)x100}{1x80-0,75x80}=41,25\)
\(\frac{\left(X-1,75\right)x100}{80-60}=41,25\)
\(\frac{\left(X-1,75\right)x100}{20}=41,25\)
\(\left(X-1,75\right)x100=41,25x20\)
\(\left(X-1,75\right)x100=825\)
\(\left(X-1,75\right)=825:100\)
\(\left(X-1,75\right)=8,25\)
\(X=8,25+1,75\)
\(X=10\)
Tham khảo nha !!!