Answer:
Laura and Rob are correct
Step-by-step explanation:
we have
39/50
1) Rob said he could divide the numerator by the denominator
so
using a calculator
39/50=0.78
Rob is correct
2) Laura said she could write an equivalent fraction with 100 as the denominator to converted into a decimal
so
Multiply by 2/2
(39/50)*(2/2)=78/100=0.78
Laura is correct
therefore
Laura and Rob are correct
Answer:
hello your question lacks the required options but i will provide a general answer to your question
answer : The mean value and the standard deviation would allow us use a Z-score
Step-by-step explanation:
mean value = 231 minutes
standard deviation ( std ) = 40 minutes
sample size = 40
The parameters that would be applicable while use Z-score are : The given mean value and the standard deviation
This is because the value of a z-score gives us an information on how far we are from the mean score i.e. number of standard deviations
+Zscore means that the score is above the average value
-Zscore means that the score is below the average value
Answer:
Step-by-step explanation:
x = 150
1/3 x = 50
x -20 = 30
x -10 = 140
Are u ok ????
Answer:
He must survey 123 adults.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the z-score that has a p-value of 
.
The margin of error is:
Assume that a recent survey suggests that about 87% of adults have heard of the brand.
This means that 
90% confidence level
So 
, z is the value of Z that has a p-value of 
, so 
.
How many adults must he survey in order to be 90% confident that his estimate is within five percentage points of the true population percentage?
This is n for which M = 0.05. So
Rounding up:
He must survey 123 adults.
Answer:
B
Explanation:
The y intercept can be read directly off of the graph, and is where the line intersects the y of the graph.
The slope (gradient) can be determined by using the equation y=mx+c, where we can substitute in the y intercept and an x and y value on the line.
y=mx+4
(2;0) is a point on the line, it is the coordinates of the x intercept (y intercept will work as well)
0=m(2)+4
m=-2
