Answer:
Step-by-step explanation:
The amount that Alexa owes after t weeks is given by a linear equation in the following format:
In which L(0) is the initial amount borrowed and b is how much is paid per week.
Alexa agreed to pay back her friend $10 per week and originally borrowed $170.
This means that, respectivelly, 
. So
Percent of red lights last between 2.5 and 3.5 minutes is 95.44% .
<u>Step-by-step explanation:</u>
Step 1: Sketch the curve.
The probability that 2.5<X<3.5 is equal to the blue area under the curve.
Step 2:
Since μ=3 and σ=0.25 we have:
P ( 2.5 < X < 3.5 ) =P ( 2.5−3 < X−μ < 3.5−3 )
⇒ P ( (2.5−3)/0.25 < (X−μ)/σ < (3.5−3)/0.25)
Since, Z = (x−μ)/σ , (2.5−3)/0.25 = −2 and (3.5−3)/0.25 = 2 we have:
P ( 2.5<X<3.5 )=P ( −2<Z<2 )
Step 3: Use the standard normal table to conclude that:
P ( −2<Z<2 )=0.9544
Percent of red lights last between 2.5 and 3.5 minutes is 
% .
Answer:
Step-by-step explanation:
Hello!
In stratified sampling, the researcher separates the population into subgroups according to the criteria established for his experiment. These subgroups will be made up of homogeneous observation units in terms of the characteristics of interest. In this case, each of the people who make up the groups will have only one of the two possible opinions (support, do not support) but not both.
When this type of sampling is performed, it is the researcher who decides what sample size you want to take, depending on various economic factors, availability of materials, access to experimental units (for example, if they are endangered animals, that is, finite populations , you cannot take very large sample sizes)
You can perform a proportionate stratified sampling and take a proportion of people who answered "yes" and a proportion of people who answered "no."
In this type of sampling, when taking a given proportion of each population, it is easier to extrapolate the results obtained to the populations. Then, if for example you must take a sample of size n = 20 where both strata correspond to half, that is to say that the stratum corresponding to "yes" will be 10 people and the stratum corresponding to "no" will be ten people.
I hope this helps!
Answer:
Hello, the correct answer to this question is letter D) 20.7%
Step-by-step explanation:
