A seller uses faulty weight in place of a 2 kg weight and earns a 25% profit. He claims that he is selling on the cost price in front of the customers but uses a faulty weight. How much error is there in the 2 kg weight to gain 25%?
(a) 350
(b) 400
(c) 450
(d) 500
Sol:
2000g×100/125=1600g
2000-1600=400g