Two counters at a fair hold ₹8,000 and ₹6,000 in change. What per cent of the larger amount must be moved to the smaller counter so that both hold the same amount?

The two together hold ₹14,000, so each must end with ₹7,000, which means ₹1,000 moves across. The question asks for that as a share of the LARGER amount: 1000/8000 = 0.125 = 12.5%. Note that only half the ₹2,000 gap has to move, because every rupee that leaves one counter also joins the other and so closes the gap twice. 25% moves the whole ₹2,000 and merely swaps the two counters round. 16 2/3% measures the ₹1,000 against the smaller counter, and 33 1/3% makes both mistakes at once (2000/6000).