Explanation
To answer the question, we will make use of the basic relationship
[tex]\begin{gathered} distance=speed\times time \\ time=\frac{distance}{speed} \end{gathered}[/tex]let Bryon speed in the motorboat be x
Since his speed in the jet ski was 10 mph faster than in the motor boat, then the speed in the jet ski will be x+10
Since his total time is 4 hours then we can set up the equation
[tex]\frac{31}{x}+\frac{18}{x+10}=4[/tex]Our task will be to solve for x
Multiplying each term by by the lowest common multiple: (x)(x+10)
[tex]31(x+10)+18(x)=4(x)(x+10)[/tex]Simplifying further
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