GMAT Quant Chapter 1: Essential GMAT Quant Skills Flashcards
Explain what the distributive property of division over additions is.
When does it work? When does it not work?
(A + C) / B
= A/B + C/B
This only works when the denominators are the same. Does not work when denominators are different.
What is the reciprocal of 0?
Trick Question! Does not exist.
What is the quickest way to simplify a complex fraction?
multiply both the numerator and the denominator of the complex fraction by the LCD, then simplify
How do you simplify complex fractions within complex fractions?
Start with the innermost fraction. Multiply the top and bottom by the LCD and then simplify. Progressively move outwards.
In the following two situations, what happens to a fraction > 0 when you:
I. add a positive constant to the numerator & denominator
II. subtract a positive constant from the numerator & denominator
I. adding a positive constant to both sides of a fraction brings that fraction closer to one
II. subtracting a positive constant from both sides of a fraction moves the fraction further away from one
How can we quickly divide two decimals?
Make the numbers easier by moving the decimal point of the divisor and move the decimal point in the other number in the opposite direction by the same number of places.
For the GMAT, when the radical is shown to square root a number, which solution is it only referring to?
The non-negative solution. We do not consider the negative square root of a number if the radical is shown.
When the GMAT asks us to compute a calculation with massive numbers, what is a shortcut we can use to answer the question quickly?
Determine the units digit not the whole answer.
What are the only units digits a perfect square can take?
Conversely, what are the units digits a perfect square can never take?
The units digit of a perfect square can be 0, 1, 4, 5, 6, 9.
The units digit of a perfect square can never be 2, 3, 7, or 8.
Does the GMAT consider 0 to be positive or negative?
Does the GMAT consider 0 to be even or odd?
Neither.
Even.
Where does an absolute value come in the order of operations?
absolute values are calculated first because they take the same priority as parentheses in PEMDAS.
How can save time when multiplying lots of numbers?
Look for pairs of numbers that when multiplied together are really easy to use. e.g. 4 * 25 = 100
How can we add or subtract really large awkward numbers such as + 999?
Use the closest really easy large number and then add the difference once you have computed the calculation.
Add 1000 then subtract 1.
What is 0! ?
What is 1! ?
1.
1.
What key principle should we keep in mind when performing calculations on the GMAT?
More work leads to greater chances of mistakes.
Always ask if we can save time before performing long calculations by hand.
