Ax=15+bx
ax-bx=15
x(a-b)=15
x=15/(a-b)
Answer:
There is a 0.57% probability that a randomly selected nanny who was placed during the last year is a male nanny (a "mannie").
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
In this problem, we have that:
Desired outcomes:
The number of male nannies selected. 24 of the nannies placed were men. So the number of desired outcomes is 24.
Total outcomes:
The number of nannies selected. 4,176 nannies were placed in a job in a given year. So the number of total outcomes 4176.
Find the probability that a randomly selected nanny who was placed during the last year is a male nanny (a "mannie").

There is a 0.57% probability that a randomly selected nanny who was placed during the last year is a male nanny (a "mannie").
Answer:
94
Step-by-step explanation:
multiply the averages by their weighted percentage
x = final exam
88(.2) + 84(.2) + 92(.4) + x(.2) = 90
solve for x
x(.2) = 90 - 71.2 = 18.8
divide both sides by 0.2
x = 94