Answer:
length = 13 ft
Width = 3 ft
Step-by-step explanation:
Width = w ft
Length = ( w +10 ) ft
Area = 39 square ft
length * width = 39
(w +10)* w = 39
w *w + 10*w = 39
w² + 10w - 39 = 0
w² + 13w - 3w - 3*13 = 0
w(w + 13) - 3(w + 13) = 0
(w + 13) (w - 3) = 0 {Ignore w + 13 , as measurement cannot be in negative}
w - 3 = 0
w = 3
length = 3 +10 = 13 ft
Answer: 0.39
Step-by-step explanation:
Given the following classification :
Heavy smokers (H) = 10%
Light smokers (L) = 20%
Non smokers (N) = 70%
Given that :
The death rates of the heavy and light smokers were five and three times that of the nonsmokers, respectively
Let probability of death = D
P(D | N) = d
P(D | H) = 5d
P(D | L) = 3d
Hence,
P(D) = [P(H) * P(D | H) + P(L) * P(D | L) + P(N) * P(D | N)]
P(D) = [0.1 * 5d + 0.2 * 3d + 0.7 * d]
P(D) = [0.5d + 0.6d + 0.7d]
P(D) = 1.8d
A randomly selected participant died over the five-year period: calculate the probability that the participant was a nonsmoker.
P(N | D) = [P(N) * P(D | N)] / P(D)
P(N | D) = 0.7d / 1.8d
P(N | D) = 0.3888
= 0.39
