stevestein wrote:The answer is (C) because both pieces of information are required to determine last year's revenue:
Revenue - Expenses = Gross Profit
(1) Provides us with this piece of the equation:
Revenue - Expenses = 4100
(2) Provides us with this information:
Revenue = 1.5 x Expenses
Let's stop right here and use my favourite DS tool: number of equations vs number of unknowns.
Here's the MOST important rule to know and love for DS:
To solve a system of n variables, one requires n distinct linear equations.
Learn that rule. Hug that rule. Love that rule so much that you marry it!
Q Stem: 1 equation, 3 variables.
(1) 1 more equation, doesn't eliminate the 2 variables we don't want: insufficient.
(2) 1 more equation, doesn't eliminate the 2 variables we don't want: insufficient.
Together: 3 variables, 3 distinct linear equations. We have enough information to answer ANY question about the system: sufficient, choose (C).
Note that no math was harmed in the solving of this question!
