Not for those of us who actually learned math before there were calculators. I'd be curious about how good Millenials and younger are about manipulating numbers and recognizing things.
The 75% one I got but I did the hard way in my head and it was a bit tricky. Some of the others were easy but tricky.
In the years B.C. (Before Calculators), you had to know how to keep track of orders of magnitude and have a general sense of whether your answer was reasonable. Most younger folks that I know have never had to do this, so they tend to take whatever comes out of the calculator as unchallenged truth. There are exceptions, though.