If this is supposed to be

Then this can simply be reduced to

by the double angle formula for cosine
You want one of the values in the ratio to be one for a unit rate. First, write out the ratio. It is 70 miles/2 hours. It's better not to include decimal numbers when you write a ratio when you can, so we're going to make the hours the unit rate. To make 2 -> 1 hour, divide both sides of the ratio by 2. 70/2 = 35.
The unit rate is 35 mi./hr.
Hope that helped you.
One pair is 4.345+4.345 (which is the pair that does not involve grouping)
The fraction equal to .66 is <span>33⁄50</span>