△ is one of operations addition, subtraction, multiplication and divis

Given: △ is one of operations addition, subtraction, multiplication and division.
To find: The value of 2△2.

Statement 1:
4△2=2. △ can be division or subraction.
So, statement 1 is insufficient.

Statement 2:
3△1=3. △ can be division or multiplication.
So, statement 2 is insufficient.

From Statement 1 and Statement 2:
We can conclude that division is the operation.

Statement 1 and Statement 2 together are sufficient.

Correct choice: C

=>

Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution.
The operation △ can be considered to be one variable. Since we have 1 variable and 0 equations, D is most likely to be the answer. So, we should consider each of the conditions on their own first.
Condition 1)
Since 4△2=2, △ is subtraction or division.
If △ is subtraction, then 2△2 = 0.
If △ is division, then 2△2 = 1.
Since we don’t have a unique solution, condition 1) is not sufficient.

Condition 2)
Since 3△1=3, △ is multiplication or division.
If △ is multiplication, then 2△2 = 4.
If △ is division, then 2△2 = 1.
Since we don’t have a unique solution, condition 2) is not sufficient.

Conditions 1) & 2)
The two conditions show that △ must be division. Thus, 2△2 = 1.
Since we have a unique solution, condition 2) is sufficient.


Therefore, C is the answer.
Answer: C

If the original condition includes “1 variable”, or “2 variables and 1 equation”, or “3 variables and 2 equations” etc., one more equation is required to answer the question. If each of conditions 1) and 2) provide an additional equation, there is a 59% chance that D is the answer, a 38% chance that A or B is the answer, and a 3% chance that the answer is C or E. Thus, answer D (conditions 1) and 2), when applied separately, are sufficient to answer the question) is most likely, but there may be cases where the answer is A,B,C or E.

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