Both a, b, and c are 3-digits integers, where a=b+c. Is the hundreds' digit of number a equal to sum of that of b and c?
a = xyz
b= lmn
d =opq
so xyz = lmn +nop
i.e 100x + 10y +z = 100l + 10m +n + 100o + 10p +q
1). Tens' digit of a=tens' digit of b+tens' digit of c
i.e y=m+p
so we have
100x + 10p + 10m +z = 100l + 10m +n + 100o + 10p +q
100x +z =100(l+o) + n+q
we cant say z=n+q coz n+q may produce a carry
INSUFF
2). Units' digit of a=units' digit of b + units' digit of c
z= n + q
same as above we wont be able to conclude
INSUFF
combine
we have
100x +n + q =100(l+o) + n+q
so x = l+o
SUFF
C
The fastest line of analysis here would be
1) Tens' digit of a=tens' digit of b+tens' digit of c
This would be true only if tens' digit of b+tens' digit of c does not produce a carry
2) Units' digit of a=units' digit of b + units' digit of c
i.e again it does not produce a carry
so in that case sum of the hunderd's digit of b & c must be equal to that of a coz if not then it would be only if the sum produces a carry which would chabge the nos to 4 digit.
Arocks can u check the OA again.
Integers
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samirpandeyit62
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jangojess
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sameer....your method is correct, however you assume that the sum of hundred's digit of B and C will give only a single digit hundred's place in A. What if there is a carry in the sum of hundred's digit??? we cant depict that info from the given stmts and SO the ans shld be E itself....
arocks...u come up wiith pretty good Qs...wht's the src for these man?? these types can come in real exam...
arocks...u come up wiith pretty good Qs...wht's the src for these man?? these types can come in real exam...
Trying hard!!!
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samirpandeyit62
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Hi jangojess,arocks
Well its given in the question that "a, b, and c are 3-digits integers" that's why I think it should be C coz if there is a carry then "a" would be 4 digit nos.
arocks the q says "Both a, b, and c are 3-digits integers" here both refers to a,b,c can u verify this.
Well its given in the question that "a, b, and c are 3-digits integers" that's why I think it should be C coz if there is a carry then "a" would be 4 digit nos.
arocks the q says "Both a, b, and c are 3-digits integers" here both refers to a,b,c can u verify this.
Regards
Samir
Samir
I get the answer A
a = xyz
b= lmn
c =opq
The only way l + o can be equal to x is when there is no carry from m + p.
Thats exactly what statement 1 says.
Statement 2 tells us abt n + q and thats not sufficient info.
a = xyz
b= lmn
c =opq
The only way l + o can be equal to x is when there is no carry from m + p.
Thats exactly what statement 1 says.
Statement 2 tells us abt n + q and thats not sufficient info.
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samirpandeyit62
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Hi Raul,
I think u are right it should be A, ya m+p should not produce a carry coz then m+p <> y, but this stmt also implicitly states that n + q should not produce a carry, otherwise m+p <> y, Stmt 2 explicitly states this, hence I was more keen for C, however Stmt 1 alone is sufficeint coz it enforces the condition on the units digit as well, so 2 is not explicitly reqd, Thanks for pointing out.
I think u are right it should be A, ya m+p should not produce a carry coz then m+p <> y, but this stmt also implicitly states that n + q should not produce a carry, otherwise m+p <> y, Stmt 2 explicitly states this, hence I was more keen for C, however Stmt 1 alone is sufficeint coz it enforces the condition on the units digit as well, so 2 is not explicitly reqd, Thanks for pointing out.
Regards
Samir
Samir
