All dictionaries are useful;
Useful books are valuable.
Dictionaries are valuable.
Univ. “books”; m = useful; x = dictionaries; y = valuable.
All x are m; All m are y. All x are y. | ∴ All x are y. |
Hence proposed Conclusion is right.
3.
No misers are unselfish;
None but misers save egg-shells.
No unselfish people save egg-shells.
Univ. “people”; m = misers; x = selfish; y = people who save egg-shells.
No m are x′; No m′ are y. No x′ are y. | ∴ No x′ are y. |
Hence proposed Conclusion is right.