Question: The ratio of boys to girls at the dance was 3:4. There were 60 girls at the dance. The teachers were 20% of the number of boys. How many people were at the dance? Think carefully first, then make a decision:
60 girls represent 4 parts, so one part of students is 60 / 4 = 15 students. There are 15 * 3 = 45 boys at the dance. The teachers at the dance are 45 * 0,2 = 9 teachers at the dance. There are 60 + 45 + 9 = 114 people at the dance. So the answer is 114.