Answer:
71°
Step-by-step explanation:
The temperature had to be at least 71° when the heater quit to be able to lose 4° and still be at least 67° when the heater is repaired.
Question is...how did someone know that the heater had failed?
Working Principle: Stratified Random Sampling
nx = (Nx/N)*n
where:
nx = sample size for stratum x
Nx = population size for stratum x
N = total population size
n = total sample size
Given:
Nx = 100
N = 1000
n = 0.5*(1000) = 500
Required: Probability of Man to be selected
Solution:
nx = (Nx/N)*n
nx = (100/1000)*500 = 50 men
ny = (Nx/N)*n
ny = (100/1000)*500 = 50 women
Probability of Man to be selected = nx/(nx + ny)*100 = 50/(50+50)*100 = 50%
<em>ANSWER: 50%</em>
Answer:

Step-by-step explanation:

hope this helps you.