You are standing on a sidewalk and watching a parade pass by. Here are the observations you make:
1. For the first 10 minutes, 80 people walk by you per minute.
2. This rate decreases by 25% for the next five minutes.
3. This rate decreases by 50% for the next five minutes.
How many people passed by you?
10 x 80 = 800 first ten minutes
80 x .75 =60 each minute x 5 300
60 x .50 = 30 each minute x5 150
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=1250 people