7.If w + z = 28, what is the value of wz ?
(1) w and z are positive integers.
(2) w and z are consecutive odd integers.
If w + z = 28
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If they were negative, then they couldn't add to positive 28sweet83 wrote:the problem does not state when the consecutive odd integers are negative or positive. if we consider negative odd integers, then should'nt the answer be C?
someone please explain.. thanks!
To examine (2) algebraically, we might let x be the smaller odd # and let x+2 be the larger odd #
We know that x + (x+2) = 28
We can solve this for x (x=13), which means the 2 numbers are 13 and 15
SUFFICIENT.
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Ricky's solution is good.
Another way to look at B would be the sum of any 2 consecutive integers or odd integers or even integers is always unique. Therefore we know we can find the two numbers and hence their product.
SUFF
Regards,
CR
Another way to look at B would be the sum of any 2 consecutive integers or odd integers or even integers is always unique. Therefore we know we can find the two numbers and hence their product.
SUFF
Regards,
CR
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Solution:
Question Stem Analysis:
We need to determine the value of wz, given that the sum of w and z is 28.
Statement One Alone:
Statement one alone is not sufficient. For example, if w = 1 and z = 27, then wz = 27. However, if w = 14 and z = 14, then wz = 196.
Statement Two Alone:
Statement two alone is sufficient since the only consecutive odd integers that add up to 28 are 13 and 15. Therefore, regardless of whether w = 13 and z = 15 OR w = 15 and z = 13, we have wz = 195.
Answer: B
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