Let ¯¯¯¯¯ab be the original integer (a,b∈N;a>0;a,b≤9)

{a+b=8¯¯¯¯¯ba=4¯¯¯¯¯ab+3⇒{a+b=8a+10b=40a+4b+3

⇒{b+a=86b−39a=3⇒{2b+2a=162b−13a=1

⇒{15a=15b=8−a⇒{a=1b=7

So, the answer is 71

Let \(\overline{ab}\) be the original integer \(\left(a,b\in N;a>0;a,b\le9\right)\)

\(\left\{{}\begin{matrix}a+b=8\\\overline{ba}=4\overline{ab}+3\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}a+b=8\\a+10b=40a+4b+3\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}b+a=8\\6b-39a=3\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}2b+2a=16\\2b-13a=1\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}15a=15\\b=8-a\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}a=1\\b=7\end{matrix}\right.\)

So, the answer is 71