By selling 20 oranges for N1.35 a trader makes a profit of 8%. What is his percentage gain or loss if he sells the same 20 oranges for N1.10?

A.
8% 
B.
10% 
C.
12% 
D.
15%
Correct Answer: Option C
Explanation
profit 8% of N1.35 = (frac{8}{100}) x N1.35 = N0.08
Cost price = N1.35 – N0.10 = N1.25
If he sells the 20 oranges for N1.10 now
%loss = (frac{text{actual loss}}{text{Cost price}}) x 100
(frac{125 – 1.10}{1.25}) x 100
= (frac{0.15 times 100}{1.25})
= (frac{15}{1.25})
= 12%