I've been making some really avoidable errors, and when I reviewed them I realized how easily these errors could be salvaged if I knew just one tiny piece of additional information (like the volume formula for a pyramid). I've skimmed through my
error log (so far) and have come up with a very simple list. Please feel free to add to this list, but let's try to keep to simple concepts someone can grasp in minutes if not less, hence the easily avoidable aspect:
1) 0's and 1's
2) Negatives
3) Fractions
4) -1, -1/2, 0, 1/2, 1 (think of this as a compiled list of 1~3; if a question does not offer a constraint, this is a good probe for substitution of all real numbers)
5) Company A has $5mil assets. Company B has $1mil assets. What's the ratio of
per capita asset of A to B. (Part vs Whole)
6) Alan and Nathan run at each other. Nathan at 5m/s, Alan at 3m/s. How fast is Alan going?
It's not 5m/s. (Keep names/orders consistent, GMAC will do this to you, on purpose)
7) A.[x-digits] * B.[y-digits] = C.[(x+y)-digits]; e.g. 2.3*4.56 = 10.488
note exceptions to this rule, however e.g. 1.5 * 28) Inscribed angle in circle = 1/2 intercepted arc (see
Inscribed Angle Theorem)
9) Pyramid (square or triangular) volume = (1/3)Bh where B is area of base and h is height
10) Cone volume = (1/3)Bh where B is area of base and h is height
11) Permitted combinations = Total combinations -
Forbidden combinations12) 400% =/= 400% increase/change. 400% of a number is equivalent to 300% increase of that number. X%Y = Y + (X-100)%Y
Let's try to get a list going, because I really think this could help a lot of people. And I'll keep working through my
error log to find more of these facepalms, so I'll be editing anything good I find along with what you guys add to the list as well.