The average weight of the 25 sacks in a godown was recorded as 46 kg. It was later found that one sack, which actually weighs 63 kg, had been entered as 38 kg. What is the correct average weight of the 25 sacks?

The recorded total is $25\times 46=1150$ kg. Only one entry was wrong, and it was 63 - 38 = 25 kg too LIGHT, so the true total is 1150 + 25 = 1175 kg and the correct average is 1175/25 = 47 kg. 45 kg pushes the 25 kg correction the wrong way (46 - 1). 48 kg applies the correction twice, once for dropping 38 and once for adding 63 - the single figure 25 already covers both. 46 kg assumes one wrong entry among 25 cannot move the average, but it moves it by exactly 25/25 = 1 kg.