Sam is driving from chicago to san francisco, a distance of 2220 miles. he covers the first 192 miles in 4 hrs. at this rate, how long will the entire trip take?

We can set it up like this:



This states that Sam can drive 192 miles in 4 hours and 2220 miles in x hours.  To solve, we can use cross-multiplication:



It will take Sam 46.25 hours to drive the whole trip, or 46 hours and 15 minutes.

Letter a i would say