To answer this
problem, we use the binomial distribution formula for probability:
P (x) = [n!
/ (n-x)! x!] p^x q^(n-x)
Where,
n = the
total number of test questions = 10
<span>x = the
total number of test questions to pass = >6</span>
p =
probability of success = 0.5
q =
probability of failure = 0.5
Given the
formula, let us calculate for the probabilities that the student will get at
least 6 correct questions by guessing.
P (6) = [10!
/ (4)! 6!] (0.5)^6 0.5^(4) = 0.205078
P (7) = [10!
/ (3)! 7!] (0.5)^7 0.5^(3) = 0.117188
P (8) = [10!
/ (2)! 8!] (0.5)^8 0.5^(2) = 0.043945
P (9) = [10!
/ (1)! 9!] (0.5)^9 0.5^(1) = 0.009766
P (10) = [10!
/ (0)! 10!] (0.5)^10 0.5^(0) = 0.000977
Total
Probability = 0.376953 = 0.38 = 38%
<span>There is a
38% chance the student will pass.</span>
Construct the perpendicular bisector of ST
2x-4(x+1)=-13
1) we solve this equation:
2x-4(x+1)=-12
2x-4x-4=-12
-2x=-12+4
-2x=-8
x=-8/-2
x=4
2) we evalute x²-1
x²-1=4²-1=16-1=15
Answer: 15
Well, you would find the perimeter adding up all of the sides. Would you please tell us what each of the sides are, or what sides are what? :)
A = 1/2 bh
A = 1/2 (21)(8)
A = 1/2 (168)
A = 84