Answer: 208.
Step-by-step explanation:
The formula to find the minimum sample size is given by :-
(1)
, where z* = critical z-value (two tailed).
= Standard deviation ( from prior study ) and E = Margin of error.
As per given , we have
Margin of error : E= 0.29
Confidence level = 85%
Significance level =
Using z-table , the critical value (two -tailed)=
As per previous study , Variance =
Now, the required minimum sample size = 
[Substitute the values in formula (1)]
[ Round to the next integer]
Hence, the minimum number of third graders that must be included in a sample = 208.
Answer:
The simplified expression is:
Step-by-step explanation:
We want to simplify:
We factor the numerator and the denominator to get:
Cancel out u-2 which is common to the numerator and the denominator yo get:
Answer: The first one is 2 2/3 and the second one is 10 1/2
Step-by-step explanation: So 2/3 divided by 1/4. First you would do keep, change, flip. Then that would give you 2/3 times 4/1. 2/3 times 4/1 would be 8/3 which can be simplified to 2 2/3. The second one 7 divided by 2/3. Again do keep, change, flip. 7 times 3/2. This would give you 21/2 when you simplify you get 10 1/2.
Answer:
x = 2 sqrt(2) - 2 or x = -2 - 2 sqrt(2)
Step-by-step explanation:
Solve for x:
x^2 + 4 x = 4
Add 4 to both sides:
x^2 + 4 x + 4 = 8
Write the left hand side as a square:
(x + 2)^2 = 8
Take the square root of both sides:
x + 2 = 2 sqrt(2) or x + 2 = -2 sqrt(2)
Subtract 2 from both sides:
x = 2 sqrt(2) - 2 or x + 2 = -2 sqrt(2)
Subtract 2 from both sides:
Answer: x = 2 sqrt(2) - 2 or x = -2 - 2 sqrt(2)
X = 2 should be the right answer
