Question

If a pendulum clock rings for 30 s at 6 o clock. for how many seconds will it ring at 12 o clock?

Answer 1

in 6 o'clock 30 s
in 12 o'clock 30 x 2 ( because in 6 rings = 30 s
in 12 o'clock 30 X 2 )
so, in 12 = 60 sec answer