420 + 65 . 4 = ( x + 175 ) : 5 + 30
420 + 260 = ( x + 175 ) : 5 + 30
680 = ( x + 175 ) :5 + 30
\(\Rightarrow\)( x +175 ) : 5 +30 = 680
\(\Rightarrow\)( x + 175 ) :5 = 680 - 30
\(\Rightarrow\)( x + 175 ) : 5 = 650
\(\Rightarrow\)( x + 175 ) = 650 . 5
\(\Rightarrow\)x + 175 = 3250
\(\Rightarrow\)x = 3250 - 175
\(\Rightarrow\)x = 3075