Two particles \(A\) and \(B\) are executing simple harmonic motion with amplitudes \(10\,\text{cm}\) and \(20\,\text{cm}\) respectively. If the time periods of two particles \(A\) and \(B\) are \(8\,\text{s}\) and \(12\,\text{s}\) respectively, then the ratio of the times taken by the particles \(A\) and \(B\) to complete \(\dfrac18^{\text{th}}\) oscillation starting from their extreme positions is