*Given
Percent of the wolves which are female - 55%
Percent of the wolves which hunt
in medium-sized packs - 20%
Percent of the wolves which are both
female and hunt in medium-sized
packs - 15%
*Solution
<u>Assuming that there is a total of one hundred wolves in the species, </u>
1. Since percent (%) means "per 100" or "for every 100" then,
a. The number of female wolves is
(55 female wolves / 100 wolves) * 100 wolves total = 55 female wolves
b. The number of wolves that hunt in medium-sized packs is
(20 wolves / 100 wolves) * 100 wolves total = 20 wolves
Note that the 20 wolves is a mixture of male and female wolves.
c. The number of female wolves that hunt in medium-sized packs is
(15 female wolves / 100 wolves) * 100 wolves total = 15 female wolves
2. Because there is a total of 55 female wolves in the species, and 15 of these wolves hunt in medium-sized packs, then the number of female wolves that do not hunt in medium-sized packs is,
55 female wolves total - 15 female wolves hunting = 40 female wolves not
in medium-sized packs hunting in medium
sized packs
3. To find the proportion, we can express the answer in terms of percent (%) or in fraction, which is usually how proportions are expressed.
For every 100 wolves, there are 40 female wolves that do not hunt in medium-sized packs. This can be expressed as a proportion of
<span> <u> 40 </u>
</span> 100
and simplified by dividing both the numerator and denominator by 10, we get,
<span><u> 40/10 </u>
</span> 100/10
<span><u> 4 </u>
</span> 10
When this is expressed in percent, we multiply the fraction or proportion by 100% to get,
<span><u> 4 </u> x 100% = 40%
</span> 10
Thus, the proportion of female wolves that do not hunt in medium sized packs is 4/10 or 0.4. When expressed as percent, this is 40%.
There is only one structure feasible for a tetrahedral molecule with such a formula, under the supposition that A is in the center of the tetrahedredon. In this case X and Y are in the vertices of the tetrahedron.
If you draw several figures changing the position of the X's and the Y around the center (A), you will see that all are equivalent.
This is the case of the product CH3Cl, named chloromethane, which, for the same reason given above, does not have isomers.