Case 1:
C.P = ₹ 75
S.P = ₹ 90
(S.P > C.P)
∴ Profit = S.P - C.P
⇒Profit=₹ (90−75)=₹ 15.
Case 2:
C.P = ₹ 28
S.P = ₹ 20
(C.P > S.P)
∴ Loss = C.P - S.P
⇒Loss=₹ (28−20)=₹ 8.
Case 3:
C.P = ₹ 40
S.P = ₹ 50
(S.P > C.P)
∴ Profit = S.P - C.P
⇒Profit=₹ (50−40)=₹ 10.
∴ProfitC.P=Profit Percent100
∴1040=Profit Percent100
% Profit = 25 %.