Dear student,
As we know that . Energy ( E ) = - 13.6 / n2 eV ( For H atom )
according to the given question : For n = 3 , Energy = - 13.6 / 9 = E or - 13.6 = 9 E ........( i )
now for n = 1 : Energy = - 13.6 / 1 = 9 E
and for n = 2 : Energy = - 13.6 / 4 = 9 E / 4
Regards