kskumar wrote:
can anyone explain the Through Weighted Avg Method?
as per my knowledge Taking extremes of Homeowners of the ratio that they have given Homeowners 5:4 -TOTAL OF 9
Taking extremes 36-------x--------45
and avg comes around 40.5 so we can solve as above to get the answer to Option (E)- 41
avigutman VeritasKarishmaYou're right that we can solve this using a weighted average,
kskumar!
Your approach isn't quite right, though. They have not given us a ratio of 5:4.
They have given us a ratio of 1:5 (where 5 ratio units represents the total number of men in the association) and a ratio of 1:4 (where 4 ratio units represent the total number of women in the association). Adding the 5 ratio units and the 4 ratio units is where you went wrong. These ratios may have different scale factors, so you can't add them. What you could do, though, if you wanted to, is infer that the number of men is some positive multiple of 5 and the number of women is some positive multiple of 4.
Now, as for solving this problem using weighted average thinking: if all 200 people were men, there would be 40 homeowners, and if all 200 people were women, there would be 50 homeowners. Therefore, the actual number of homeowners must be one of the integers inside that range, exclusive (why exclusive? because the question is nonsensical if there are only members of one gender). Now that we know the number of owners is at least 41 and at most 49, we can answer the question with ease.