Answer:
a) (1215, 1297)
b) (1174, 1338)
c) (1133, 1379)
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 1256
Standard Deviation, σ = 41
Empirical Rule:
- Also known as 68-95-99.7 rule.
- It states that almost all the data lies within three standard deviation for a normal data.
- About 68% of data lies within 1 standard deviation of mean.
- About 95% of data lies within two standard deviation of mean.
- About 99.7% of data lies within 3 standard deviation of mean.
a) range of years centered about the mean in which about 68% of the data lies
68% of data will be found between 1215 years and 1297 years.
b) range of years centered about the mean in which about 95% of the data lies
95% of data will be found between 1174 years and 1338 years.
c) range of years centered about the mean in which about all of the data lies
All of data will be found between 1133 years and 1379 years.
Answer:
Option is right
Step-by-step explanation:
Given that bella want to know what the students at her school think of her show. which is the BEST group to survey to find this information
For getting accurate results she must select a random sample without bias
For this option a will not serve since she selects only students she recognizes.
Option B may not be right, as during show on the face they may not give correct opinion
C is right as a random sample is taken
D is wrong as the first 30 students may not be at random.
So option C is right
Answer:
y= 11x -5
Step-by-step explanation:
I believe you rearrange it to get y on one side of the equation so,
2y= 22x-10
and then divide 2 on both sides to get,
y=11x-5
Answer:
The answer is C.
Step-by-step explanation:
The equivalents to 1/4 are 2/8, 3/12, 4/16 etc. So the fractions after 1/4 are higher than 1/4. Then you count how many 'x's are in the columns for those measurements and you will get 6.
Answer:
33 1/3 L of the 40% solution, 16 2/3 L of the 25% solution
Step-by-step explanation:
Set up two equations...
Let x represent the number of Liters of the 40% solution
Let y represent the number of Liters of the 25% solution
We need 50 liters total, so
x + y = 50
and we need the 50 L to be 35% solution, so
0.4x = 0.25y = 0.35(50)
Solve the first equation for one variable...
x = 50 - y (subtract y from both sides in equation 1)
Now substitute that value into the second equation...
0.4(50 - y) + 0.25y = 17.5 (x becomes 50 - y, 0.35(50) = 17.5)
Now solve for y...
20 - 0.4y + 0.25y = 17.5
-0.15y = -2.5
y = 16.66666667
y = 16 2/3 L
So we need to plug that into the first equation to find 'x'
x + 16 2/3 = 50
x = 50 - 16 2/3
x = 33 1/3
