Explain simply why 180 is the correct answer to: Susy goes to a large school with 800 students, while Sarah goes to a smaller school with only 300 students. At the start of the school year, Susy had 100 social media followers. She gained 40 new followers in the first week of the school year, half that in the second week, and half of that in the third week. Sarah only had 50 social media followers at the start of the year, but she gained 90 new followers the first week, a third of that in the second week, and a third of that in the third week. After three weeks, how many social media followers did the girl with the most total followers have?. Explanation:
After one week, Susy has 100 + 40 = 140 followers. In the second week, Susy gains 40 / 2 = 20 new followers. In the third week, Susy gains 20 / 2 = 10 new followers. In total, Susy finishes the three weeks with 140 + 20 + 10 = 170 total followers. After one week, Sarah has 50 + 90 = 140 followers. After the second week, Sarah gains 90 / 3 = 30 followers. After the third week, Sarah gains 30 / 3 = 10 followers. So, Sarah finishes the three weeks with 140 + 30 + 10 = 180 total followers. Thus, Sarah is the girl with the most total followers with a total of 180.