Answer:
Step-by-step explanation:
Total = 50
Males = 20
Females = 30
a) P(exactly 1 female) = P(1 female , 2 male)
(30C1 * 20C2) / (50C3) = 30*190/19,600 = 0.2908
b) P(at least 2 males) = 1 - (P(0 males) + P(1 males))
= 1 - 30C3 * 20C0/50C3 - 30C2 * 20C1/50C3
= 1 - 4060*1/19,600 - 435*20/19,600 = 6840/19600 = 0.3489
Answer:
b is correct
Step-by-step explanation:
Answer:
It takes 75 years for the investment to quadruple in value
Step-by-step explanation:
Simple Interest
This is a simple interest problem.
The simple interest formula is given by:

In which E is the amount of interest earned, P is the principal(the initial amount of money), I is the interest rate(yearly, as a decimal) and t is the time.
After t years, the total amount of money is:

In this question:
4% simple interest per year, so I = 0.04.
Quadruple:
t when T = 4P.
The interest earned is:



Now we find the time.





It takes 75 years for the investment to quadruple in value
If y=8-x then you can plug that into the equation like 7=2-(8-x). When you distribute the equation becomes 7=2-8+x. Once you combine like terms the equation becomes 7=-6+x. Then you subtract 6 from both sides, which gives you 13=x.
To find y just put 13 where x was in the first equation. Y=8-13.
Y=-5
X=13