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If a, b, and c are integers. Is abc+ab+c an odd? 1) ac=odd 2) ab=odd
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13 Mar 2017, 23:43
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If a, b, and c are integers. Is abc+ab+c an odd? 1) ac=odd 2) ab=odd
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If a, b, and c are integers. Is abc+ab+c an odd? 1) ac=odd 2) ab=odd
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14 Mar 2017, 00:06
D 1)ac is odd 2cases : b is even Then even +even + odd > odd When b is odd then too the Sun is odd
2 ) ab is odd cases when c is odd . Then the entire Sun is odd When c is even then too the sum is odd
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Re: If a, b, and c are integers. Is abc+ab+c an odd? 1) ac=odd 2) ab=odd
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14 Mar 2017, 02:26
If a, b, and c are integers. Is abc+ab+c an odd?
1) ac=odd 2) ab=odd
ac=odd i.e a and c both are odd case 1 : when b is odd abc=odd*odd=odd ab=odd*odd c=odd so sum will also be odd
case 2: when b is even abc=even ab=even c=odd so sum will be odd so Statement 1 is sufficient
same concept can be applied to statement 2 as well so Answer is D



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Re: If a, b, and c are integers. Is abc+ab+c an odd? 1) ac=odd 2) ab=odd
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15 Mar 2017, 05:47
St 1: ac is odd. that means a is odd and c is odd. no idea about b. INSUFFICIENT St 2: ab is odd. that means a is odd and b is odd. no idea about c. INSUFFICIENT St 1 & St 2: a,b,c is odd. therefore abc is odd, ab is odd and c is odd therefore abc +ab +c = odd +odd +odd = odd. ANSWER Option C
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If a, b, and c are integers. Is abc+ab+c an odd? 1) ac=odd 2) ab=odd
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15 Mar 2017, 18:32
If a, b, and c are integers. Is abc+ab+c an odd?
1) ac=odd
It means that both a & c are odd
Let a=c=1
abc+ab+c=b+b+1=2b+1=Even+ Odd=Odd
Sufficient
2) ab=odd
It means that both a & b are odd
Let a=b=1
abc+ab+c=c+1+c=2c+1=Even+odd=odd
Sufficient
Answer: D



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Re: If a, b, and c are integers. Is abc+ab+c an odd? 1) ac=odd 2) ab=odd
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27 Mar 2017, 18:19
ziyuen wrote: If a, b, and c are integers. Is \(abc+ab+c\) an odd?
1) \(ac=odd\) 2) \(ab=odd\) OFFICIAL SOLUTION If you modify the original condition and the question, from abc+ab+c=odd?, ab(c+1)+c=odd?, you get the same result as c=odd?. This is because if c=odd, you get c+1=even, then ab(c+1)+c=ab(even)+odd=even+odd=odd, hence yes. In the case of con 1), if ac=odd, the condition is yes and sufficient. In the case of con 2), by the law of “CMT 4(B: if you get A or B too easily, consider D)”, when ab=odd, ① If c=odd, you get ab(c+1)+c=odd(odd+1)+odd=odd(even)+odd=odd, hence yes. ② If c=even, you get ab(c+1)+c=odd(even+1)=odd(odd)+even=odd, hence, in the case of ① and case of ②, it is always yes and sufficient. Therefore, the answer is D.
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Re: If a, b, and c are integers. Is abc+ab+c an odd? 1) ac=odd 2) ab=odd
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28 Mar 2017, 00:37
If a, b, and c are integers. Is abc+ab+c an odd?
1) ac=odd 2) ab=odd
1... odd*b + odd*b + odd ( as odd * odd = odd so a and c will e odds) if b is odd then odd + odd + odd = odd and if b is even then, even + even + odd = odd sufficient 2... odd *c +odd + c if c is odd then, odd + odd + odd = odd and if c is even then, even + odd + even = odd sufficient hence, d



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Re: If a, b, and c are integers. Is abc+ab+c an odd? 1) ac=odd 2) ab=odd
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12 Jul 2018, 05:25
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Re: If a, b, and c are integers. Is abc+ab+c an odd? 1) ac=odd 2) ab=odd
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12 Jul 2018, 05:25






