A cloth seller measures with a rod that is only 96 cm long but bills every such length as one full metre. A customer pays for 25 metres. The cloth he actually gets is short by what per cent of the cloth he paid for?

25 rod-lengths = $25\times 96=2,400$ cm = 24 metres, so he is short by 1 metre. The words 'of the cloth he paid for' fix 25 metres as the base: 1/25 = 0.04 = 4%. 4.17% is 1/24 - the shortfall measured against what he RECEIVED, which is the seller's side of the same gap, not the customer's. 96% is the share he did get. 24% mistakes the 24 metres received for a percentage.