#17 - The advanced technology of ski boots and bindings has

[Adam Tyson]

I'm sorry, Dancingbambarina, but I don't understand what you're saying or asking here. Answer D is incorrect because we know nothing about the total number of skiers in either year, or anything about any changes in those total numbers. The number of skiers could have gone up, or down, or stayed the same. We only know about the odds of an injury occurring either on the slopes or off. That's a percentages idea, while answer D is about numbers. Since we know nothing about those numbers, this answer could be true, and since we are looking for something that cannot be true, it's out.

The other question you are referring to is about direct proportions, with one thing increasing as another thing increases. That's not happening in this question. We don't have any information about the number of injuries always being proportional to the number of skiers. In fact, what they are telling us is that the proportion has decreased. That's a very different relationship, although they do both involve numerical concepts.

For anyone curious about that other question, you can find it discussed here: viewtopic.php?f=597&t=6355