GMAT Quant Chapter 6: General Word Problems Flashcards
What two profit equations does the GMAT assume we know?
Profit = total revenue - total cost
Profit = Total revenue - (total fixed costs + total variable costs)
How do we solve salary indifference problems?
Indifference occurs when the final pay is equal.
Set each option equal to each other and solve
How do we calculate someone’s wage
Wage =
total amount paid
/
total hours worked
How do we calculate the equalization of wages?
Make the changes to both wages then set the changed wage formulas to each other and solve
What you take from one quantity you give to another.
How do we calculate simple interest?
What must we make sure matches up
simple interest = principal x rate x time
The untis for the rate and the units for time, e.g. both are in years
What is the difference between simple and compound interest?
Compound interest includes the interest earned in each period whereas simple interest doesn’t
What is the compound interest formula?
A =
P (1 + R/n)^nt
P is principal
R is interest rate per year
T is number of years
N is number of compounding periods
What is the linear growth formula?
Fn = kn + p
Fn is the final value
k is the growth constant
n is number of growth period
p is original value before growth
What is the exponential growth formula?
End Growth =
V(G)^n
V is initial value
G is growth factor
n is number of periods
what must we know to determine the amount of growth?
The growth driver
What must we remember about the amount of decay as the decaying goes on for longer?
Decay happens the most at the start and gets slower and slower
How do we solve consecutive integer word problems?
Write the expressions algebraically.
x, x + 1, x + 2
e.g. multiples x, x + 5, x + 10
How do we solve mixture word problems?
Create a matrix and solve for the unknowns
define the 3 following components for each
I. Components
II. Units of components
III. Quantity of each component
How do we solve for we mixtures?
The final row of the matrix is always a combination
How should we think about objects in a line problems?
If a person is the mth person from the front.
If another person is the nth person from the back.
Total number in line is n + m -1
Make sure you never double count.
