Carcass wrote:
At a certain school, the ratio of students to teachers is 9:2, and the ratio of teachers to administrators is 5:3. Which of the following could be the total number of students at the school?
(Indicate all that apply.)
80
90
120
180
200
\(\frac{S}{T} = \frac{9}{2}\) \(\frac{T}{A} = \frac{5}{3}\)
Making T equal by taking LCM;
\(\frac{S}{T} = \frac{45}{10}\) \(\frac{T}{A} = \frac{10}{6}\)
\(S : T : A\) = \(45 : 10 : 6\)
This means, S must be a multiple of 45
Hence, option B and D