An app collects an integer product rating from 1 to 5 from each buyer every day. The daily average is the average of the ratings given that day; the cumulative average is the average of all ratings given on or before that day. The cumulative average rating was 3.0 at the end of Day 1 and 3.1 at the end of Day 2. The bar chart shows the distribution of the ratings given on Day 2. The following is known about Day 3. 1. 100 buyers gave ratings on Day 3. 2. The modes of the Day 3 ratings were 4 and 5. 3. The number of buyers giving each rating was a non-zero multiple of 10. 4. The same number of buyers gave ratings of 1 and of 2, and that number was half the number who gave a rating of 3.
How many buyers gave ratings on Day 1?