Question

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.

Answer 1

317.52 mi/h

Step-by-step explanation:

Distance covered = 1000 m

Time taken = 7.045 s

Convert distance to mi

`1\ mile=1609.34\ meters\\\Rightarrow 1\ meter=(1)/(1609.34\ miles)\\\Rightarrow 1000\ m=(1000)/(1609.34)\ miles`

Convert time to hours

`1\ hour=60\ minutes* 60\ seconds=3600\ seconds\\\Rightarrow 1\ second=(1)/(3600)\ hour\\\Rightarrow 7.045=(7.045)/(3600)\ hours`

So, speed of the boat

`((1000)/(1609.34))/((7.045)/(3600))=317.52\ mi/h`

Speed of the boat is 317.52 mi/h

Answer 2

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