A man purchases some oranges at the rate of 3 for ₹40 and the same quantity at the rate of 5 for ₹60. If he sells all the oranges at the rate of 3 for ₹50, then find his gain or loss percent (to the nearest integer).

32% profit

                Qty     :     Price

Buy₁ ⇒       3       :      40      ..........(i)

Buy₂ ⇒       5       :      60      ..........(ii)

ATQ, making qty equal⇒ (i) × 5 & (ii) × 3

                Qty     :     Price

Buy₁ ⇒     15      :      200

Buy₂ ⇒     15      :      180    

Buy  ⇒      30      :      380      ( Buy₁ + Buy₂)

Sale ⇒      3        :       50       (multiply by 10 to make Qty equal)  

Sale ⇒      30      :      500

So, C.P. = 380 and S.P. = 500

⇒ Profit = 500 - 380 = 120

Profit % = \(\frac{120}{380}\) × 100 = 31.5% = 32%