conversations.from: human
conversations.value: Can you give me some step-by-step instructions for this math problem: A bus has a capacity of 200 people. When it departed Chengli city, it had 20 people. On the first stop, 40 people entered the bus. On the second station, 3/4 of the total number of people who entered the bus at the first station entered the bus. If the number of passengers on the bus doubled at the third station, calculate the total number of people required to fill the remaining spaces on the bus.
conversations.from: assistant
conversations.value: If the number of passengers increased by 3/4 times the number that entered the bus on the first station, 3/4 * 40 people = 30 people entered the bus on the second station.
  After the second station, the number of people on the bus was 20 people initially on the bus + 40 who entered at the first station + 30 who entered at the second station= 90 people.
  The number of people doubled at the third station, which is 90 people * 2 = 180 people.
  If the bus has a capacity of 200, the number of people required to fill the bus is 200 people - 180 people = 20 people