I wrote it somewhere else where I can’t copy and paste so hope this works!
Answer:
115mm
Step-by-step explanation:
5/x = 3/69
5/x = 1/23
5*23 = x
115 = x
You make them to improper fractions then you find a greatest common factor and then go from there
Total of ratio 5+7=12
60/12 = 5
For boys 5x5 = 25 boys in her class
(For girls 7x5 = 35)