Answer:

Step-by-step explanation:
we have:

we also have:

from (1)(2) => proven
Answer:
7,173
x = 7
Step-by-step explanation:
Within the question it gives two examples.
x = 0 corresponds to 2000
x = 1 corresponds to 2001
If you pay close attention the x-value is always the same as the last digits in the year. So with 2007 the last digit is 7, which then leads us to determine that
x = 7
f (x) = -327 (7) + 9462
f (x) = -2289 + 9462 = 7173
Answer:
(a)
The values of X can be 0, 1, 2 , ..., 10 . So, X is a discrete random variable.
(b)
The distribution of X is Binomial distribution with the parameters n = 10 and p = 0.2
(c)
Probability that no one or one person will be injured = P(X = 0) + P(X = 1)
= 10C0 * 0.20 * (1 - 0.2)10-0 + 10C1 * 0.21 * (1 - 0.2)10-1
= 0.810 + 10 * 0.2 * 0.89
= 0.3758096
(d)
Average value of X = np
Average value of X = 10 * 0.2 = 2
(e)
Variance of X = np(1-p)
Variance of X = 10 * 0.2 * (1 - 0.2) = 1.6
(f)
Number of ways in which 2 people gets injured = 10C2 = 10! / ((10-2)! 2!) = (10 * 9) / (2 * 1) = 45
Assume the best player got injures, number of ways in which one people out of remaining 9 people gets injured = 9C1
= 9! / ((9-1)! 1!)
= 9
Probability that the best player got injured = Number of ways in which 1 people gets out of 9 and best person gets injured / Number of ways in which 2 people gets injured
= 9 / 45
= 0.2
To find the fraction of the grouo that passed both exams, we need to first convert 75% into a fraction:
75%
=75/100
=3/4
We can then mutiply the fraction above by the students who passed the psychological exam:
3/4×3/5
=9/20
Therefore the answer is 9/20.
Hope it helps!
Answer:
0.0066%
Step-by-step explanation: