Researchers studying long-term changes in regional mouse populations h

Any explanation of this 3rd ques?

Can anyone explain Q1? not sure how the calculations arrived at

If their numeral value remained the same from 1990 to 2005, then we can say that maybe their total population not remained the same as species X is A percent of total population.

Hence if total population is increased then surely the A value is decreased accordingly to make the effect constant (i.e. X population in 2005) and vice versa.

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We can also say that all other options are getting rejected easily. A and E are directly out.

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The difference seems higher from 1975 to 1990 , not sure why OA says otherwise

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Can anyone please explain q2 and @Sajjid1994 please provide the official explanation.

pls explain Q3

To find the total number of mice in a region, we need to divide the given number of "X" by the percentage provided in the second table. Let's calculate the values:

For the year 1960:
Given number of X: 947
Percentage: 3.356%
Total number of mice in 1960 = 947 / 3.356 = 282 (rounded to the nearest whole number)

For the year 1975:
Given number of X: 144
Percentage: 0.351%
Total number of mice in 1975 = 144 / 0.351 = 410 (rounded to the nearest whole number)

For the year 1990:
Given number of X: 968
Percentage: 2.051%
Total number of mice in 1990 = 968 / 2.051 = 472 (rounded to the nearest whole number)

Based on these calculations, we can observe that there is an increase in the total number of mice from 1960 to 1975 (282 to 410). Therefore, the answer to the first part of the question is "Yes."

For the second part of the question, we can see that the total population of the region in 1990 is approximately 478 (as calculated above). Since this is greater than the total number of mice in 1990 (472), the answer is also "Yes."

However, for the third part of the question, if we compare the total number of mice in 1975 (410) to the total number in 1990 (472), we can see that there is an increase in population from 1975 to 1990. Therefore, the answer is "No."

Q3 :
Despite Species X remaining constant from 1990 to 2005, there were species amongst the total population, Which their population might have kept changing between 1990 to 2005, this could have led to population not remaining constant.

Isn't this against the main premisse of the question that "they can make fairly accurate estimations about the total regional mouse populations."?

Shouldn't the Total number of mice in 1960 = 947000 / 0.03356 ?

plz explain Q2?

MartyMurray
chetan2u
KarishmaB
ScottTargetTestPrep

Could anyone please help understand Q3 and its solution ? Thanks in advance­

please solve for question 2

­What a sophisticated approach. Awesome

Responding to a pm:
You don't need any calculations in this question. Just look at the data given and also on what is not given!

Question 3:


Species X pop of TY is constant from 1990 to 2005 so in 2005 also it will be about 970k. In 1990, it is about 2% of total mouse pop. We don't know what percent it will be in 2005 because we are not given that this percentage remains the same too.
When Species X pop was about 950k in 1960, it was 3.3% of total pop. So in 2005, a similar figure could represent any percent of the total mouse pop.

So 2nd statement is supported: The total mouse population of TY may not have remained roughly constant between 1990 and 2005.
Since Species X could be any percent of total pop, the total pop could be any figure. So it may not have remained constant.
ANSWER

Look at the other statements:

TY most likely does not share a border with any other region in the study.

I do not know whether Species X moves from one region to another. The table gives me no indication. In fact, if anything, it shows that when the pop reduces, it reduces or stays steady in most regions. When it increases, it increases or stays steady in most regions. So there is no data to support anything about whether one region shares border with another region.


TY had the largest total mouse population of any region in the study in 2005.

No info about total mouse population in 2005 of any region. As we see, the percentages (Species X as a percent of total mouse pop) change with time so even if for some regions we know species X pop in 2005, we cannot say anything about total pop.

The total mouse population of EW grew more than twice as fast between 1990 and 2005 as the total mouse population of TY did.

As we discussed about, no info about total mouse pop in 2005. ­

TY was the only region in the study in which the Species X population remained relatively steady between 1990 and 2005.

No data to support this. It may have remained steady in IQ or JR or PS etc. ­

Kindly answer all 3 in depth

cathyjiang04
I agree. Why is no one dividing each % by 100?