Answer :
Use your units !
"Period" is time . . . 12 seconds.
"Frequency" how often . . . " ___ PER time". Time is in the denominator.
"12 seconds per wave" means
1 wave / 12 seconds
= ( 1 / 12 ) (wave/second)
= 0.08333... wave per second
= 1/12 Hz.
Hello!
Data:
T (period) = 12 s
f (frequency) = ? (waves/second)
Formula:
[tex]f = \dfrac{1}{T}[/tex]
Solving:
[tex]f = \dfrac{1}{T}[/tex]
[tex]f = \dfrac{1}{12}[/tex]
[tex]\boxed{\boxed{f \approx 0.083\:waves/second}}\end{array}}\qquad\quad\checkmark[/tex]
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I Hope this helps, greetings ... Dexteright02! =)