That would be (180 mi)/(20 mi/in) = 180/20 in = 9 in.
If you pay attention to the units, you can write it however you feel comfortable. Another way to do it is this
(180 mi)*((1 in)/(20 mi)) = 180/20 in = 9 in
The main thing is to use to advantage the ratio (1 in)/(20 mi) or (20 mi)/(1 in).
If you pay attention to the units, you can write it however you feel comfortable. Another way to do it is this
(180 mi)*((1 in)/(20 mi)) = 180/20 in = 9 in
The main thing is to use to advantage the ratio (1 in)/(20 mi) or (20 mi)/(1 in).