A train starts from station P with ‘n’ number of passengers. At station Q, 20% of the passengers get down and 50 passengers get on. At station R, 40% of the passengers get off and 10 passengers get in. If a total of 520 passengers are left on the train, find the value of ‘n’.
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 1000.
Let initial passengers = n
At Station Q:
20% get down → 0.2n
Remaining: n - 0.2n = 0.8n
50 passengers get in, Total = 0.8n + 50
At Station R:
40% get down →
40% of (0.8n + 50) = 0.4(0.8n + 50) = 0.32n + 20
Remaining = (0.8n + 50) - (0.32n + 20) = 0.48n + 30
10 passengers get in, Total = 0.48 + 30 + 10 = 0.48 + 40
Final number of passengers = 520
⇒ 0.48n + 40 = 520
⇒ 0.48n = 480
⇒ n = 100