Given, for each radio C.P.=Rs600
For the first Radio,
Profit % =S.P.1−C.P.C.P×100=12 %
=>S.P.1−600600×100=12 %
=>S.P.1−600=72
=>S.P.1=Rs672
Given, total Loss =−Rs25
=>TotalS.P.−Total.C.P.=−25
=>672+S.P.2−1200=−25
=>S.P.2−528=−25
=>S.P.2−503
Hence, he sold the second radio for Rs 503