\(a\) is \(10\) less than \(x\) and \(b\) is \(3\) less than \(y.\) If the ratio of \(x\) to \(b\) is \(2\) to \(3,\) and the ratio of \(x\) to \(y\) is \(7\) to \(12,\) then what is the ratio of \(a\) to \(y?\)
A) \(-\dfrac16\)
B) \(-\dfrac14\)
C) \(\dfrac16\)
D) \(\dfrac7{12}\)
E) \(\dfrac73\)
Answer: C
Source: Princeton Review