If b is prime and the symbol # represents one of the following operations: addition, subtraction, multiplication, or division, is the value of b # 2 even or odd?
1) (b # 1) # 2 = 5
# = + ; b+3=5; b=2.(Prime)
# = - ; b-3=5; b=8.(Non Prime)
# = * ; b*2=5; b!=Integer.(Non Prime)
# = % ; b%2=5; b=10(Non Prime)
b # 2 = 2+2 = 4(Even) - Sufficient!
2) 4 # b = 3 # (1 # b) and b is even
Only even prime number is 2.
b # 2 = 2+2 = 4(Even) - Sufficient!
IMO D
TOUGH DS
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neelgandham
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Anil Gandham
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vaibhavgupta
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D it is!gmatblood wrote:If b is prime and the symbol # represents one of the following operations: addition, subtraction, multiplication, or division, is the value of b # 2 even or odd?
1) (b # 1) # 2 = 5
2) 4 # b = 3 # (1 # b) and b is even
1) almost immediately knew only value of b would be 2 and # is addition.
2) b is even meant leave the rest and the answer would be even !
If OA is A, IMO B
If OA is B, IMO C
If OA is C, IMO D
If OA is D, IMO E
If OA is E, IMO A
FML!! :/
If OA is B, IMO C
If OA is C, IMO D
If OA is D, IMO E
If OA is E, IMO A
FML!! :/
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HSPA
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A is not the answer because for addition, sub and multiplication B#2 is even and for division B =10 and B/2 = 5 odd. We cannot judge B#2 based on 1st option
B+2 = 4; B-2 = 6; B/2 = 5.. even even odd.. A is bad
The tough thing is that 1 and 2 options have paranthesis too.. these take precedence as well..
B+2 = 4; B-2 = 6; B/2 = 5.. even even odd.. A is bad
The tough thing is that 1 and 2 options have paranthesis too.. these take precedence as well..
neelgandham wrote:If b is prime and the symbol # represents one of the following operations: addition, subtraction, multiplication, or division, is the value of b # 2 even or odd?
1) (b # 1) # 2 = 5
# = + ; b+3=5; b=2.(Prime)
# = - ; b-3=5; b=8.(Non Prime)
# = * ; b*2=5; b!=Integer.(Non Prime)
# = % ; b%2=5; b=10(Non Prime)
b # 2 = 2+2 = 4(Even) - Sufficient!
2) 4 # b = 3 # (1 # b) and b is even
Only even prime number is 2.
b # 2 = 2+2 = 4(Even) - Sufficient!
IMO D
First take: 640 (50M, 27V) - RC needs 300% improvement
Second take: coming soon..
Regards,
HSPA.
Second take: coming soon..
Regards,
HSPA.
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neelgandham
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I am afraid you got the question wrong, the question can be rephrased to. What is # and what is the value of B? From the 1st statement we found that # = + and B = 2HSPA wrote:A is not the answer because for addition, sub and multiplication B#2 is even and for division B =10 and B/2 = 5 odd. We cannot judge B#2 based on 1st option
The tough thing is that 1 and 2 options have paranthesis too.. these take precedence as well..
neelgandham wrote:If b is prime and the symbol # represents one of the following operations: addition, subtraction, multiplication, or division, is the value of b # 2 even or odd?
1) (b # 1) # 2 = 5
# = + ; b+3=5; b=2.(Prime)
# = - ; b-3=5; b=8.(Non Prime)
# = * ; b*2=5; b!=Integer.(Non Prime)
# = % ; b%2=5; b=10(Non Prime)
b # 2 = 2+2 = 4(Even) - Sufficient!
2) 4 # b = 3 # (1 # b) and b is even
Only even prime number is 2.
b # 2 = 2+2 = 4(Even) - Sufficient!
IMO D
# = + ; b+3=5; b=2.(Prime)
# = - ; b-3=5; b=8.(Non Prime)
# = * ; b*2=5; b!=Integer.(Non Prime)
# = % ; b%2=5; b=10(Non Prime)
No other sign or No other value satisfies the equation.
Anil Gandham
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HSPA
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Okay I missed that B is prime.. sorry for the confusion..
neelgandham wrote:I am afraid you got the question wrong, the question can be rephrased to. What is # and what is the value of B? From the 1st statement we found that # = + and B = 2HSPA wrote:A is not the answer because for addition, sub and multiplication B#2 is even and for division B =10 and B/2 = 5 odd. We cannot judge B#2 based on 1st option
The tough thing is that 1 and 2 options have paranthesis too.. these take precedence as well..
neelgandham wrote:If b is prime and the symbol # represents one of the following operations: addition, subtraction, multiplication, or division, is the value of b # 2 even or odd?
1) (b # 1) # 2 = 5
# = + ; b+3=5; b=2.(Prime)
# = - ; b-3=5; b=8.(Non Prime)
# = * ; b*2=5; b!=Integer.(Non Prime)
# = % ; b%2=5; b=10(Non Prime)
b # 2 = 2+2 = 4(Even) - Sufficient!
2) 4 # b = 3 # (1 # b) and b is even
Only even prime number is 2.
b # 2 = 2+2 = 4(Even) - Sufficient!
IMO D
# = + ; b+3=5; b=2.(Prime)
# = - ; b-3=5; b=8.(Non Prime)
# = * ; b*2=5; b!=Integer.(Non Prime)
# = % ; b%2=5; b=10(Non Prime)
No other sign or No other value satisfies the equation.
First take: 640 (50M, 27V) - RC needs 300% improvement
Second take: coming soon..
Regards,
HSPA.
Second take: coming soon..
Regards,
HSPA.
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Gokhra
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neelgandham wrote:If b is prime and the symbol # represents one of the following operations: addition, subtraction, multiplication, or division, is the value of b # 2 even or odd?
1) (b # 1) # 2 = 5
# = + ; b+3=5; b=2.(Prime)
# = - ; b-3=5; b=8.(Non Prime)
# = * ; b*2=5; b!=Integer.(Non Prime)
# = % ; b%2=5; b=10(Non Prime)
b # 2 = 2+2 = 4(Even) - Sufficient!
2) 4 # b = 3 # (1 # b) and b is even
Only even prime number is 2.
b # 2 = 2+2 = 4(Even) - Sufficient!
IMO D
Based on 1) you can prove that "#" represents addition and that b is 2.
I don't think you can do that with based on equation 2. As per equation 2, "#" can represent either subtraction or addition. And also because b is even, b must be 2. So b#2 could either be 4 or 0. INSUFFICIENT. So IMO A
What is the OA?
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HSPA
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Option 2 says that B is prime and B is even.. there is only one value that B can be = 2
2 is the only even prime number... HTH
2 is the only even prime number... HTH
Gokhra wrote:neelgandham wrote:If b is prime and the symbol # represents one of the following operations: addition, subtraction, multiplication, or division, is the value of b # 2 even or odd?
1) (b # 1) # 2 = 5
# = + ; b+3=5; b=2.(Prime)
# = - ; b-3=5; b=8.(Non Prime)
# = * ; b*2=5; b!=Integer.(Non Prime)
# = % ; b%2=5; b=10(Non Prime)
b # 2 = 2+2 = 4(Even) - Sufficient!
2) 4 # b = 3 # (1 # b) and b is even
Only even prime number is 2.
b # 2 = 2+2 = 4(Even) - Sufficient!
IMO D
Based on 1) you can prove that "#" represents addition and that b is 2.
I don't think you can do that with based on equation 2. As per equation 2, "#" can represent either subtraction or addition. And also because b is even, b must be 2. So b#2 could either be 4 or 0. INSUFFICIENT. So IMO A
What is the OA?
First take: 640 (50M, 27V) - RC needs 300% improvement
Second take: coming soon..
Regards,
HSPA.
Second take: coming soon..
Regards,
HSPA.
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Gokhra
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Agreed, but the question doesn't ask about b, it asks about b#2. Without knowing what "#" represents, how can we answer whether b#2 is even or odd?HSPA wrote:Option 2 says that B is prime and B is even.. there is only one value that B can be = 2
2 is the only even prime number... HTH
Gokhra wrote:neelgandham wrote:If b is prime and the symbol # represents one of the following operations: addition, subtraction, multiplication, or division, is the value of b # 2 even or odd?
1) (b # 1) # 2 = 5
# = + ; b+3=5; b=2.(Prime)
# = - ; b-3=5; b=8.(Non Prime)
# = * ; b*2=5; b!=Integer.(Non Prime)
# = % ; b%2=5; b=10(Non Prime)
b # 2 = 2+2 = 4(Even) - Sufficient!
2) 4 # b = 3 # (1 # b) and b is even
Only even prime number is 2.
b # 2 = 2+2 = 4(Even) - Sufficient!
IMO D
Based on 1) you can prove that "#" represents addition and that b is 2.
I don't think you can do that with based on equation 2. As per equation 2, "#" can represent either subtraction or addition. And also because b is even, b must be 2. So b#2 could either be 4 or 0. INSUFFICIENT. So IMO A
What is the OA?
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saketk
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A very logical thing we should do here is NOT to check for different Mathematical expressions other than MULTIPLY. (the only exception here is b= 2, which can be quickly checked)gmatblood wrote:If b is prime and the symbol # represents one of the following operations: addition, subtraction, multiplication, or division, is the value of b # 2 even or odd?
1) (b # 1) # 2 = 5
2) 4 # b = 3 # (1 # b) and b is even
Can someone tell me why I said so? That logic will make this question very easy.
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saketk
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Good question. Well if you know b is 2 then the next best thing to do is put that value in the given expression [4 # b = 3 # (1 # b].Gokhra wrote: Agreed, but the question doesn't ask about b, it asks about b#2. Without knowing what "#" represents, how can we answer whether b#2 is even or odd?
This way you will be able to find what is #. But, I like your question. the explanation provided by other poster does not include that part. For example if # is DIVIDE then 2/2 = 1 [ which is NOT even]
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saketk
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Well this is my third post in this thread..saketk wrote:Good question. Well if you know b is 2 then the next best thing to do is put that value in the given expression [4 # b = 3 # (1 # b].Gokhra wrote: Agreed, but the question doesn't ask about b, it asks about b#2. Without knowing what "#" represents, how can we answer whether b#2 is even or odd?
This way you will be able to find what is #. But, I like your question. the explanation provided by other poster does not include that part. For example if # is DIVIDE then 2/2 = 1 [ which is NOT even]
I missed your penultimate post.
ZERO is in-fact EVEN.
An integer n is called *even* if there exists
an integer m such that n = 2m, and *odd* if n+1 is even. From this,
it is clear that 0 = (2)(0) is even.
So, the second statement is also sufficient.
