Question 1204542
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The water level at an ocean inlet has a depth, d in meters, that varies with the time, t, 
in hours after midnight, according to the equation d = sin(2π(t-4/12.4)) + 6. 
What is the water depth at 5:30 ? To the nearest hundredth of a metre.
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<pre>
I will assime that 5:30 in this problem is 5:30 am;  so t= 5.5 hours  in the formula.


Then to get the answer, you should substitute t= 5.5 into the given formula


    d = sin(2pi*((5.5-4)/12.4))) + 6 = 6.69 meters  (approximately).    <U>ANSWER</U>
</pre>

This problem is a matter of substituting a value into the formula.



Notice that in your formula in the post, a pair of parentheses is missed, 
so I added it based on my common sense and the rules of Math grammar.