Symbol * denote to be one of the operations add, subtract, multiply, or divide. Is (6*2)*4=6*(2*4)?
1). 3*2>3 2). 3*1=3
Number Systems
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Hi sukhman,
For this type of symbolism question, we need to make sure to be thorough (that we've considered all the possibilities).
We're told that the symbol is 1 of 4 possible operations. We're asked if (6*2)*4 = 6*(2*4)? This is a Yes/No question.
Fact 1: 3*2 > 3
Here, the * symbol COULD be addition or multiplication
If it's addition, then (6+2)+4 DOES = 6+(2+4). The answer to the question is YES
If it's multiplication, then (6x2)4 DOES = 6(2X4). The answer to the question is YES.
Fact 1 is SUFFICIENT
Fact 2: 3*1 = 3
Here, the * symbol COULD be multiplication or division
From Fact 1, we know that multiplication gives us a YES answer.
If it's division, then (6/2)/4 = 3/4 and 6/(2/4) = 12 ..... 3/4 does NOT = 12, so the answer to the question is NO.
Fact 2 is INSUFFICIENT.
Final Answer: A
GMAT assassins aren't born, they're made,
Rich
For this type of symbolism question, we need to make sure to be thorough (that we've considered all the possibilities).
We're told that the symbol is 1 of 4 possible operations. We're asked if (6*2)*4 = 6*(2*4)? This is a Yes/No question.
Fact 1: 3*2 > 3
Here, the * symbol COULD be addition or multiplication
If it's addition, then (6+2)+4 DOES = 6+(2+4). The answer to the question is YES
If it's multiplication, then (6x2)4 DOES = 6(2X4). The answer to the question is YES.
Fact 1 is SUFFICIENT
Fact 2: 3*1 = 3
Here, the * symbol COULD be multiplication or division
From Fact 1, we know that multiplication gives us a YES answer.
If it's division, then (6/2)/4 = 3/4 and 6/(2/4) = 12 ..... 3/4 does NOT = 12, so the answer to the question is NO.
Fact 2 is INSUFFICIENT.
Final Answer: A
GMAT assassins aren't born, they're made,
Rich
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Target question: Does (6*2)*4 = 6*(2*4)?sukhman wrote:Symbol * denote to be one of the operations add, subtract, multiply, or divide.
Is (6*2)*4 = 6*(2*4)?
1) 3*2 > 3
2) 3*1 = 3
Statement 1: 3*2 > 3
Check each operation.
Does * stand for addition?
3 + 2 > 3. So, * MIGHT denote addition
Does * stand for subtraction?
3 - 2 < 3. So, * does NOT denote subtraction
Multiplication?
3 x 2 > 3. So, * MIGHT denote multiplication
Division?
3/2 < 3. So, * does NOT denote division
So, * stands for EITHER addition OR multiplication
If * stands for addition, then (6*2)*4 EQUALS 6*(2*4)
If * stands for multiplication, then (6*2)*4 EQUALS 6*(2*4)
So, both cases yield the same answer to the target question (Yes).
Since we can answer the target question with certainty (the answer is YES), statement 1 is SUFFICIENT
Statement 2: 3*1 = 3
Does * stand for addition?
3 + 1 ≠3. So, * does NOT denote addition
Does * stand for subtraction?
3 - 1 ≠3. So, * does NOT denote subtraction
Multiplication?
3 x 1 = 3. So, * MIGHT denote multiplication
Division?
3/1 = 3. So, * MIGHT denote division
So, * stands for EITHER multiplication OR division
If * stands for multiplication, then (6*2)*4 EQUALS 6*(2*4)
If $ stands for division, then (6*2)*4 DOES NOT equal 6*(2*4)
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT
Answer = A
Cheers,
Brent