Question 25
HardOriginal questionAssume the statements are true.
Statements: All feathers are balloons. Some feathers are not lanterns.
Conclusions:
I. Some balloons are not lanterns.
II. Some lanterns are not balloons.
Show the answer and explanation
CorrectNot quiteAnswer A
Correct answer: A
Explanation
Pick a feather that is not a lantern. It is a feather, so it is also a balloon. That balloon is not a lantern, so some balloons are not lanterns: I follows.
For II, draw the lantern circle entirely inside the balloon circle (away from that feather). All statements hold and every lantern is a balloon, so II is not definite.
Only I follows.
Worth noting
'Some X are not Y' cannot be reversed into 'Some Y are not X'. Conclusion II is exactly that reversed form.
- Concept
- Carrying a Some … not up to a bigger group; Some … not is not reversible
- Typical timeTypical
- 110 s
- Your timeYours
- —
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