Three pencils cost the same as two erasers. Four erasers cost the same as one ruler. Therefore, pencils are more expensive than rulers.
举一反三
- A country produces only pencils and erasers. Pencil production is allocatively efficient if the marginal ________ of a pencil equals the marginal ________ of ________. A: cost; benefit; an eraser B: cost; cost; an eraser C: benefit; benefit; an eraser D: benefit; cost; a pencil
- There _______ a book , two pencils and three notebooks on the desk.
- There ____ a pen, two pencils and three books on the desk.
- Yesterday I caught sight of a dress _____ cost far less than one of exactly the same style in the other shop.
- In a two-minute presentation, you won’t have time to develop more than __________ main points. A: one or two B: two or three C: three or four D: four or five