The ratio of boys to girls at the assembly was 5 to 4. If there were 180 students at the assembly, how many girls were there? Explain why your answer is reasonable.
The ratio b : g = 5 : 4 the sum of the ratio = 5 + 4 = 9
Find the number of girls girls = the ratio of girls/the sum of the ratio × the sum of students girls = 4/9 × 180 girls = (4 × 180)/9 girls = 720/9 girls = 80
