Question

There were 256 people at a fundraiser. When the event was over, half of the people who remained left every 5 minutes. How long after the event ended did the last person leave?

a) 5 minutes
b) 10 minutes
c) 15 minutes
d) 20 minutes

Answer 1

To determine how long after the event ended the last person left, we need to divide the original number of people by 2 every 5 minutes until we reach 0. This process takes 10 minutes. Therefore, the correct answer is b) 10 minutes.

Step-by-step explanation:

To determine how long after the event ended the last person left, we need to calculate the total number of people who left over time. Since half of the people who remained left every 5 minutes, we can divide the original number of people (256) by 2 every 5 minutes until we reach 0.

Starting with 256, after 5 minutes there would be 128 people remaining. After another 5 minutes, there would be 64 people remaining. This pattern continues until we reach 0.

Based on this, we can conclude that it takes 10 minutes for the last person to leave. Therefore, the correct answer is b) 10 minutes.