And vs. Or in this OG SC

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And vs. Or in this OG SC

by saad.ahmed » Sat Feb 12, 2011 9:22 am
I know this is a very easy question and I should be getting it right, but the last two times I came across this question, I made the same error. Someone please help!

From the OG 12th edition, page 693 #17, I am having a challenging time figuring out why the proper usage is "Or" vs. "And".... here is the question:

The commission has directed advertisers to restrict the use of the word "natural" to foods that do not contain color or flavor additives, chemical preservatives, or nothing that has been synthesized.

a - or nothing that has been
b - or that has been
c - and nothing that is
d - or anything that has been
e - and anything

Can anyone explain why "Or" is the logical conjunction here?

Thanks,

Saad

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by hja379 » Sat Feb 12, 2011 10:53 am
Use of 'and' changes the meaning of the sentence.

For eg: I want to buy a car, a bike and a plane.
The sentence above means that I want to buy all three at once.

Take this one for instance: I want to eat an apple, an orange or a pear.
This one means, I only want to eat one of the three.

Hope that helps.
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by GMATGuruNY » Sat Feb 12, 2011 2:44 pm
saad.ahmed wrote:I know this is a very easy question and I should be getting it right, but the last two times I came across this question, I made the same error. Someone please help!

From the OG 12th edition, page 693 #17, I am having a challenging time figuring out why the proper usage is "Or" vs. "And".... here is the question:

The commission has directed advertisers to restrict the use of the word "natural" to foods that do not contain color or flavor additives, chemical preservatives, or nothing that has been synthesized.

a - or nothing that has been
b - or that has been
c - and nothing that is
d - or anything that has been
e - and anything

Can anyone explain why "Or" is the logical conjunction here?

Thanks,

Saad
When or is negated, it means "and": not X or Y means not X and not Y.

Thus, in answer choice D (the correct answer), foods that do not contain color or flavor additives, chemical preservatives, or anything that has been synthesized means foods that do not contain color additives and do not contain flavor additives and do not contain chemical preservatives and do not contain anything that has been synthesized.
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by saad.ahmed » Sat Feb 12, 2011 5:20 pm
Mitch,

Thank you for the well explained answer! I was able to find a wikipedia article that explains this as well:

https://en.wikipedia.org/wiki/De_Morgan's_laws

Thanks for chiming in.

-Saad

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by sachindia » Mon Oct 01, 2012 8:22 am
Hi Mitch,
When or is negated, it means "and": not X or Y means not X and not Y.
Is this a mathematical concept? I vaguely remember having studied this in my maths class.
Regards,
Sach