2011 AMC 8 Problems/Problem 14
Contents
[hide]Problem
There are students at Colfax Middle School, where the ratio of boys to girls is . There are students at Winthrop Middle School, where the ratio of boys to girls is . The two schools hold a dance and all students from both schools attend. What fraction of the students at the dance are girls?
Video Solution
https://youtu.be/rQUwNC0gqdg?t=697
Solution
At Colfax Middle School, there are girls. At Winthrop Middle School, there are girls. The ratio of girls to the total number of students is
Solution 2 (Guess and Check)
Since we know there are kids at Colfax Middle School and we know the ratio of boys to girls is , we can use guess and check to find the number of girls at the dance (and vice versa). and . Now that the ratios sum to and , we know that in Colfax there are girls and in Winthrop, there are girls. total girls and total people.
Video Solution 1 by SpreadTheMathLove
https://www.youtube.com/watch?v=mYn6tNxrWBU
See Also
2011 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 13 |
Followed by Problem 15 | |
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All AJHSME/AMC 8 Problems and Solutions |
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