Hana sold 4/7 of her stamp collection for $28. How much would she have earned from selling the entire collection? Let's think first. Chain of thought:
Hana sold 4 / 7 of her collection for $28, so 1 / 7 of her collection represents: 28 / 4 = $7. And as a result, the entire collection represents: 7 * 7 = $49.
Therefore, the answer is 49.