Need help with this percentage question please

1. How much thicker is the heavy-duty aluminum foil than the regular aluminum foil? Calculate this by dividing the larger thickness by the smaller thickness. This will give you a value that shows what percentage thicker the heavy-duty foil is than the regular foil. Express your answer as a percent. [Hint: Here’s an example.  Let’s say that you divide your larger value by your smaller value and get 1.75. This means that the larger value is 75% larger than the smaller value.] (3 pts)

 

^ above is the teacher's example. I don't understand the 1 in 1.75 disappearing from the percentage. Shouldn't it be 175%?

 

My numbers are:

0.0037/0.0017=2.1764705882

then the percentage would be 217.64705882%