There are 3 girls to every 4 boys, or to every 7 people. Therefore the percentage of girls to people is approximately 43%. So there are 36 girls.
The choir has 36 girls based on the ratio of girls to boys, which is 3:4. With a total of 84 members, we can calculate the number of girls by finding the value of one part in the ratio and multiplying it by the number of girl parts. Therefore, there are 36 girls in the choir.
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