Let X be the national sat score. X follows normal distribution with mean μ =1028, standard deviation σ = 92
The 90th percentile score is nothing but the x value for which area below x is 90%.
To find 90th percentile we will find find z score such that probability below z is 0.9
P(Z <z) = 0.9
Using excel function to find z score corresponding to probability 0.9 is
z = NORM.S.INV(0.9) = 1.28
z =1.28
Now convert z score into x value using the formula
x = z *σ + μ
x = 1.28 * 92 + 1028
x = 1145.76
The 90th percentile score value is 1145.76
The probability that randomly selected score exceeds 1200 is
P(X > 1200)
Z score corresponding to x=1200 is
z = 
z = 
z = 1.8695 ~ 1.87
P(Z > 1.87 ) = 1 - P(Z < 1.87)
Using z-score table to find probability z < 1.87
P(Z < 1.87) = 0.9693
P(Z > 1.87) = 1 - 0.9693
P(Z > 1.87) = 0.0307
The probability that a randomly selected score exceeds 1200 is 0.0307
Answer:
my day is going good just got on the school
Answer:
The best option for him would be a real interest rate of 5%.
Step-by-step explanation:
The nominal interest rate is the one that represents the percentage of increase of the money that is in a certain investment, without discounting the depreciation due to inflation or the payment of taxes.
On the other hand, the real interest rate is the one that represents the real increase in the money invested, after discounting inflation and any taxes to be paid.
Therefore, the best option for Oscar would be to invest his $ 4,000 in a savings account with a real interest rate of 5% per year.
Answer:
56 multiplied by 9 = 504
Step-by-step explanation:
55.8 rounded is 56, and 9.12 rounded is 9
Answer:
The solution is (3,13) and (-1,-3). So none of the mentioned options is correct.
Step-by-step explanation:
Given that


Now, by susbstituting the value of 'y' from equation i to equation ii, we get






Now by factorization, equation iii can be written as



x = 3 and x = -1
By putting the values of x in equation i, we get
y = 4(3) + 1
y = 12 +1
y = 13
and
y = 4(-1) + 1
y = -4 +1
y = -3
Therefore, the solution is (3,13) and (-1,-3). So none of the mentioned options is correct.