Question

At the banquet, the ratio of the number of girls is 5 : 3. Halfway through the banquet, 20 boys leave and the ratio becomes 5:4. How many girls are at the banquet?

Answer 1

`(5)/(8)x-20=(5)/(9)x\\-20=(-5)/(72)x\\x=288\\(3)/(8)(288)\\108`

108 girls