If of of is 64 and of of is 12.5, what is of ?
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This one wrecked me on the first pass. I kept trying to set up some giant equation with all three percents before realizing you can chain them much more simply.
Same here, took me way too long to see the pattern lol
Totally agree, the triple percent is what trips people up
Is the trick here to convert x% of x% of x% into a fraction of x^3? I got to x^3 = 640000 but then got stuck on simplifying. Anyone else feel like the numbers get ugly fast?
Yeah the cube root is the messy part, I just tried to keep it in fraction form.
I did the same and then had to back out at the end, the y part is easier on its own though.
Wait, are we supposed to treat the second equation as y% of y% of y (not y%)? That difference matters a lot and I almost missed it.
Yes exactly, that's the trap. One less percent sign changes everything.
The answer choices are a huge hint here. Only one of them is a clean power-of-ten-ish magnitude, so if you estimate roughly you can eliminate most of them without doing all the algebra.
Good point, I should've looked at the choices before burning 4 minutes on the math.
What it tests
Your ability to compute percentage change, percentage of a whole, and to work backwards from a final value.
Common trap
Treating successive percentage changes as additive — a 10% rise then a 10% fall is not back to the start.