can someone explain why the conclusion cannot inferred?

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Look at syllogism from veritas prep

All widgets are steel.
Some widgets are red.
Therefore, some steel widgets are not red.


it is mentioned that the conclusion is not "must be true".

can someone explain the reason of why the conclusion cannot be inferred from the above premises?
Source: — Critical Reasoning |

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by Brent@GMATPrepNow » Tue Dec 29, 2015 5:59 am
Mechmeera wrote:Look at syllogism from veritas prep

All widgets are steel.
Some widgets are red.
Therefore, some steel widgets are not red.


it is mentioned that the conclusion is not "must be true".

can someone explain the reason of why the conclusion cannot be inferred from the above premises?
"some" means "at least 1"
So, the premise can be rewritten as "At least 1 steel widget is red"
This means that it's possible for ALL steel widgets are red.
So, we cannot conclude that some steel widgets are not red

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Brent
Brent Hanneson - Creator of GMATPrepNow.com
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