Lesson 2, HW, Reading Comp. Passage #7, Q. #6

[mariahenain]

I'm still not clear on why choice D is the correct answer for number 6. I chose answer choice B, but was lost with how to eliminate the incorrect answers.

[AthenaDalton]

Hi Maria,

Thanks for your question!

Here's how we can put a numerical estimate on the number of secondary occultation event reports: in lines 37 - 41, we learn that such reports have become "so common . . . that they are now simply too numerous for them all to be accurate."

Then in lines 42 - 47, we learn that even under perfect conditions, at most 1 in 100 asteroids could have observable secondary occultation events. So this sets up a reasonable "floor" that, at most 1 out of 100 of these reports could feasibly be accurate. If we have far more than 1 secondary event report per 100 primary events, then we've exceeded the boundaries of what could possibly be accurate reports. That's how we can select answer choice (D).

With respect to answer choice (B); it's a tempting choice because it mentions 1 out of 1000, a number that is mentioned in the passage. Here's how we can rule it out. On lines 46 - 47, the passage tells us that 1 out of every 100 could be an accurate ratio of primary events to secondary events, but if asteroids' satellite systems resemble planetary systems, the ratio could drop to 1 out of every 1000. The passage doesn't resolve for certain whether 1 out of 100 or 1 out of 1000 is the right ratio -- it appears that, based on the best science we have, we still don't know. So taking 1 out of 100 as the most generous estimate is the best way to go here. If we're not sure if it's 1 out of 100 or 1 out of 1000, we still know for sure that if we're getting 90 reports per 100 we're way off base.

I hope this makes sense! Good luck studying!

Athena Dalton