Answer:
E(F)=200
V(F)=100
Step-by-step explanation:
(a) Let F be the amount he spends on falafel sandwiches over the next 400 days. Find E[F] and V(F).
If we analized his expenses in falafel sandwiches, we know he buys a $1 sandwich with aprobability of 50%.
If we call the random variable D the daily expense in falafel sandwiches, it is a Bernoulli variable with p=0.50.
If F is the sum of the daily expenses D during the 400 days, then we can say it is a binomial variable with p=0.5 and n=400.
Then we can calculate the expected value of F as:
![E(F)=nE(D)=400*0.5=200](https://tex.z-dn.net/?f=E%28F%29%3DnE%28D%29%3D400%2A0.5%3D200)
The variance of F is then
![V(F)=n*V(D)=n*p(1-p)=400*0.5*(1-0.5)=400*0.25=100](https://tex.z-dn.net/?f=V%28F%29%3Dn%2AV%28D%29%3Dn%2Ap%281-p%29%3D400%2A0.5%2A%281-0.5%29%3D400%2A0.25%3D100)
The answer is 12. The digit 2 is 2 times more than 1, so it matches the first part. 12 + 9 = 21. If you switch the digits of 12 around, you will get 21. So the answer is 12.
To answer this question you will need to be able to calculate compound interest. The following formula can be used to do this:
A = P(1 + r/n)^nt
A stands for the amount you will have after a period of time.
P stands for the Principal; $1750 in this case
r/n stands for the rate over the number of times the interested is compounded per year (in your case, it will be 0.0425/1)
^nt stands for "to the power of" the number of years you will be compounding the interest. In this case it is 15
Let's put it all together:
A = 1750 (1+0.0425/1)^15
A = $3267.22 is approximately the new amount after 15 years
$3267.22-$1750 = $1517 is the interest accrued
The answer is 12 because the lines of the parrellel shape he’ll come across each other
Answer:
30
Step-by-step explanation:
i believe that the 13 is there to throw you off. anyway to solve just do 5•12=60
60÷2=30 so 30 is area of triangle