The average weight of 20 persons sitting in a boat had some value. A new person added to them whose weight was 48 kg only. Due to his arrival, the average weight of all the persons decreased by 5 kg. Find the average weight of first 20 persons?
Options.
A) 55  B) 56  C) 57  D) 58  E) 59

Rationale: 20 x + 48 = 21 ( x – 5 ) x = 57 answer : c
Answer: C