Step-by-step explanation:
Answer:
a) 33.33%)
b) 135 minutes
c) 8.66 min
d) 50%
Step-by-step explanation:
a) the probability for a uniform distribution is
P(b<X<a) = (a-b)/(c-d) , where c and d are the maximum and minimum values
therefore the probability that the flight is more than 140 minutes ( and less than 150 since it is the maximum value)
P(140<X<150) = (a-b)/(c-d) = (150-140)/(150-120) = 10/30 = 1/3 (33.33%)
b) the mean (expected value) for a uniform probability distribution is
E(X) = (c+d)/2 = (120+150)/2 = 135 minutes
c) the standard deviation for a uniform probability distribution is
σ²(X)= (c-d)²/12 = (150-120)²/12 = 75 min²
σ = √75 min² = 8.66 min
b) following the same procedure as in a)
P(120<X<135) = (a-b)/(c-d) = (135-120)/(150-120) = 15/30 = 1/2 (50%)
Answer:
A = 23.6 units^2
Step-by-step explanation:
Let the base be 8 (as shown).
Find the height of the triangle: Find the supplement of the 100 degree angle; it is (180 - 100), or 80 degrees. The side "opposite" this 80-degree angle is the height of the triangle:
height
sin 80 degrees = ---------------
6
and so the height of the triangle is h = 6 sin 80 degrees, or 5.91 units.
The area of the triangle is found using A = (1/2)(base)(height), which here amounts to:
A = (1/2)(8 units)(5.91 units), or
A = 23.64 units^2, or A = 23.6 units^2