Quote:
At a certain high school, there are three sports: baseball, basketball, and football. Some athletes at this school play two of these three, but no athlete plays in all three. At this school, the ratio of (all baseball players) to (all basketball players) to (all football players) is 15:12:
18. How many athletes at this school play baseball?
Statement (1): 40 athletes play both baseball and football, and 75 play football only and no other sport
Statement (2): 60 athletes play only baseball and no other sport
Obs.: my solution is for the "15:12:
18" version, slightly different that the original (first) post presented in this topic. Obviously the reasoning is identical.
Nice example of the
Venn diagrams ("overlapping sets") and the
k technique together!
\(15:12:18 = 5:4:6\,\,\,\,\,\, \Rightarrow \,\,\,\,\,\,\left\{ \matrix{\\
\,{\rm{Baseball}} = 5k \hfill \cr \\
\,{\rm{Basketball}} = 4k \hfill \cr \\
\,{\rm{Football}} = 6k \hfill \cr} \right.\,\,\,\,\,\,\,\left( {k > 0} \right)\)
\(? = 5k\,\)
We go straight to (1+2): a
BIFURCATION will guarantee that the correct answer is (E).

This solution follows the notations and rationale taught in the GMATH method.
Regards,
Fabio.