Solution:
$$\eqalign{
& {\text{Time}}\,{\text{from}}\,7\,a.m.\,to\,4.15\,p.m. = 9\,hrs\,15\,\min . = \frac{{37}}{4}hrs \cr
& 3\,\min .\,5\,sec.\,{\text{of}}\,{\text{this}}\,{\text{clock}} = 3\,min.\,{\text{of}}\,{\text{the}}\,{\text{correct}}\,{\text{clock}} \cr
& \Rightarrow \frac{{37}}{{720}}\,hrs\,{\text{of}}\,{\text{this}}\,{\text{clock}} = \frac{1}{{20}}\,hrs\,{\text{of}}\,{\text{the}}\,{\text{correct}}\,{\text{clock}} \cr
& \Rightarrow \frac{{37}}{4}\,hrs\,{\text{of}}\,{\text{this}}\,{\text{clock}} \cr
& = \left( {\frac{1}{{20}} \times \frac{{720}}{{37}} \times \frac{{37}}{4}} \right)\,hrs\,{\text{of}}\,{\text{the}}\,{\text{correct}}\,{\text{clock}} \cr
& = 9\,hrs\,{\text{of}}\,{\text{the}}\,{\text{correct}}\,{\text{clock}} \cr
& \therefore {\text{The}}\,{\text{correct}}\,{\text{time}}\,{\text{is}}\,9\,hrs\,after\,7\,a.m.\,i.e.,\,4\,p.m. \cr} $$
