Given that,
Total cost price of an old motor cycle is
C.P.=12500+3000
C.P.=15500rs.
Selling price of an old motor cycle is
S.P.=18000rs.
We know that,
Profit=S.P.−C.P.
Profit=18000−15500
Profit=2500rs.
Therefore,
profit%=profitC.P.×100
profit%=250015500×100
profit%=2500155=16.12%