The world speed record on water was set on October 8, 1978 by Ken Warby of Blowering Dam, Australia. If Ken drove his motorboat a distance of 1000 m in 7.045 s, how fast was his boat moving in mi/h.

First convert Meters into miles as the answer is required in miles/ h

1000m = 0.62 mi

Now, convert second into hours
7.45s = 0.0001 hr

The speed of the boat would be
v = 0.62/0.0001
=317.52 mi/hr

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shirleywashington shirleywashington · Answer 2 · 2019-09-03T08:50:31+02:00

Answer:

317.52 mi/h

Explanation:

Distance covered = 1000 m

Time taken = 7.045 s

Convert distance to mi

[tex]1\ mile=1609.34\ meters\\\Rightarrow 1\ meter=\frac{1}{1609.34\ miles}\\\Rightarrow 1000\ m=\frac{1000}{1609.34}\ miles[/tex]

Convert time to hours

[tex]1\ hour=60\ minutes\times 60\ seconds=3600\ seconds\\\Rightarrow 1\ second=\frac{1}{3600}\ hour\\\Rightarrow 7.045=\frac{7.045}{3600}\ hours[/tex]

So, speed of the boat

[tex]\frac{\frac{1000}{1609.34}}{\frac{7.045}{3600}}=317.52\ mi/h[/tex]

Speed of the boat is 317.52 mi/h