The code is 200 because they went under the sea to get the key to work.
When you divide two fractions, you actually just flip one over (it's reciprocal) and multiply them.

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Use the recriprocal of
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Multiply (3 x 8) and (4 x 1)
</span>

Divide
6
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= 6</span>
3(x + 8) = 17....distribute the 3 thru the parenthesis
3x + 24 = 17...subtract 24 from both sides
3x = 17 - 24
3x = -7...divide both sides by 3
x = -7/3 or -2 1/3 <===
Is C because it can be multiplied by 0.5