Question

One pendulum ticks 57 times in 58 sec, while another ticks 608 times in 609 sec. If they started together, then how often will they tick together in the first hour?

• A. $47$
• B. $53$
• C. $57$
• D. $67$

Answer 1

The correct option is C $57$

LCM of $\frac{58}{57}$ and $\frac{609}{608}$ is $\frac{19}{1218}$
In 1 hour, they will tick together $=3600\times \frac{19}{1218}=56.16$ times after the first stroke.
$\Rightarrow 57$ times per hour (approx.)