I belive it's 5.

Because it's Distance divided by Time, because your finding speed.
Answer: 82
Simply pug in 6 for 

<em>Hope this helps and have a great day!!!</em>
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Two whole numbers whose least common denominator is 36 could be many different pairs: 1 and 36, 2 and 36, 3 and 36, 4 and 36, 4 and 18, 4 and 9, 6 and 36, 9 and 36, 9 and 12, 12 and 36, 12 and 18, 18 and 36, and lastly 36 and 36.
If you want fractions in simplest form, with different denominators, and with an LCD of 36, I would go with 4/5 and 9/13.
I think the reason these work is because 5, 13, and 36 are all pairwise relatively prime (meaning the LCD of any two of them is their product), and because the LCD of 4 and 9 is 36, like I said earlier.
If 1 mile = 1.609 km then we can use it as the conversion factor in the following way, remembering that the equation has to be set so that the miles cancel with miles.
4.5 miles =

⇒ 7.2405 km