A population of game ducks at a western lake contains 55 males to every 45 females, while a population of game ducks ...
kaori-watanabeMay 16, 2020
Adult duck
Hi, I am wondering the word adult in the answer A. In the premise, it did not say whether dusk are adult or not, it just said ducks. If ducks are mixed with adult and young ducks, we cannot conclude lower percentage of adult duck in eastern (or maybe western) unless we know the ratio of adult and young ducks. Could you tell me what is wrong in my thought?
Replies
Create a free account to read and
take part in forum discussions.
The key to answering this question comes from the inference in the last sentence:
"Becaue there are appreciably more males among adult ducks than among young ducks, we can infer that, the greater the disparity in overall sex ratios, the greater the percentage of older male ducks in the population."
You said that we need to know the ratio of adult ducks to young ducks in order to answer the question. We do know the ratio, because it is tied to the gender ratio. Remember, this is a "must be true" question, so we accept everything as fact, including the inference at the end that provides the relationship between age and gender.
The conclusion is based on the premise that there are "more males among adult ducks than among young ducks." Here, the word adult is used, and a contrast is established between young and adult ducks. From this, it is safe to assume that "older male ducks," as used in the conclusion, is referring to adult male ducks.
