Do you have a picture I can use for reference?
0.074n = 74
multiply both sides by 1000 to make the process simpler
74n = 74000
divide both sides by 74
n = 1000
GIVEN
1) Females outnumber males by 3 to 2.
2) There are 1770 people in the city.
SOLUTION
Let the number of males be x and the number of females y. Therefore, the total number of people can be written to be:

If there are 3 females for every 2 males, we have that:

We can substitute equation (2) into equation (1) and solve for y:

Dividing both sides by 5, we have

There are 1062 females in the county.
The answer is C. 3 is an element of A n B