We have $${\frac{{\mathtt{a}}}{{\mathtt{b}}}} = {\frac{{\mathtt{c}}}{{\mathtt{d}}}}$$
Prove that $${\frac{\left({\mathtt{a}}{\mathtt{\,-\,}}{\mathtt{3}}{\mathtt{\,\times\,}}{\mathtt{b}}\right)}{\left({\mathtt{5}}{\mathtt{\,\times\,}}{\mathtt{b}}\right)}} = {\frac{\left({\mathtt{c}}{\mathtt{\,-\,}}{\mathtt{3}}{\mathtt{\,\times\,}}{\mathtt{d}}\right)}{\left({\mathtt{5}}{\mathtt{\,\times\,}}{\mathtt{c}}\right)}}$$
+23245 If a/b = c/d
then subtract 3 from both sides:
---> a/b - 3 = c/d - 3
which becomes: a/b - 3b/b = c/d - 3d/d
---> (a - 3b)/b = (c - 3d)/d
Multiply both sides by 1/5:
---> (a - 3b)/(5b) = (c - 3d)/(5d)
Did you mistype the problem?
