It is 165 I hope this helps :)
Answer: 36
Since the sum of the ratios is 5+7=12
the total number of students must be divisible by 12
The only number within the given range is 36
Step-by-step explanation:
there are a lot of typos and missing info in your problem and answer option definition.
based on what I understood the answer should be
"the second answer option".
this is where A and B have an arc angle (or inner angle at the center of the circle) of 60°.
one could see the 3rd answer to be right too, as the angle between A and B at Y is also 60°.
but I don't think this is really the meaning of this question here.