Each M-type unit will increase the base memory capacity of a certain

VERITAS PREP OFFICIAL SOLUTION:

Question Type: What Is the Value? This question asks for a specific number for the base memory capacity of the computer.

Given information from the question stem: Each M-type unit will increase base capacity by 3 megabytes.

Statement 1: 2 M-types units will increase the computer’s base memory by 300%. From the fact we know that this is a total addition of 6 megabytes. So “6 = 3x,” where x is the current total base memory of the computer in megabytes. “x = 2.” This statement is sufficient, so the answer is either A or D.

Statement 2: The ratio of total memory capacity after adding 2 M-types units to the total memory capacity after adding 1 M-type unit is “1.6: 1.” Therefore 6 (which is 2M-types units) + x (the current base memory) = 1.6 (3 +x). Therefore “6 + x = 4.8 + 1.6x.” You can see that you have just one variable and you will be able to solve for x, so there is no need to do so. This is sufficient as well.

The correct answer is D.

Each M-type unit will increase the base memory capacity of a certain computer by 3 megabytes. What is the base memory capacity, in megabytes, of the computer?

(1) 2 M-type memory units will increase the computer’s base memory by 300 percent --> x + 6 = 4x --> x = 2. Sufficient.

Note that increase by 300% equals to 4 times increase.

(2) The memory capacity of the computer after 2 M-type memory units are added to the base memory capacity is 1.6 times the memory capacity after 1 M-type memory unit is added to the base memory capacity --> x + 6 = 1.6(x + 3) --> x = 2. Sufficient.

Answer: D.

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