Answer:
97 students must be randomly selected for IQ tests.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]
Now, we have to find z in the Z-table as such z has a p-value of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
The Standard Deviation is 15.
This means that [tex]\sigma = 15[/tex]
How many statistics students must be randomly selected for IQ tests if we want 95% confidence that the sample mean is within 3 IQ points of the population mean?
This is n for which M = 3. So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]3 = 1.96\frac{15}{\sqrt{n}}[/tex]
[tex]3\sqrt{n} = 1.96*15[/tex]
Simplifying both sides by 3
[tex]\sqrt{n} = 1.96*5[/tex]
[tex](\sqrt{n})^2 = (1.96*5)^2[/tex]
[tex]n = 96.04[/tex]
Rounding up(as with a sample size of 96 the margin of error will be slightly above 3):
97 students must be randomly selected for IQ tests.
[tex]a2 \div a - b + b2 \div b - a[/tex]
Answer:
0
Step-by-step explanation:
Given
a² ÷ a - b + b² ÷ b - a ← perform the division calculations
= a - b + b - a ← collect like terms
= 0
Answer:
0
Step-by-step explanation:
=a^2/a-b+b^2/b-a
=here denominator which divides a^2 and b^2 gets cancelled
=a-b+b-a
=+a-a and +b -b gets cancelled
and answer is 0
help with this please
Answer:
( x + 2 ) and ( x - 11 )
Step-by-step explanation:
x² - 9x - 22 = 0
x² + 2x - 11x - 22 = 0
x ( x + 2 ) - 11 ( x + 2 ) = 0
( x + 2 ) ( x - 11 ) = 0
Factors of x² - 9x - 22 are ( x + 2 ) and ( x - 11 ).
Answer:
( x - 11 ) ( x + 2 )
Step-by-step explanation:
x² - 9x - 22 = 0
→ Write 2 factors which multiply to -22 and add to -9
-11 and 2
→ Put the factors into brackets
( x - 11 ) ( x + 2 )
Each (hypothetical) data set below represents some readings on span gas. Assume the Gauss model, with errors following the normal curve. However, bias may be present. In each case, make a t-test to see whether the instrument is properly calibrated or not. In one case, this is impossible. Which one, and why?
a. 71, 68, 79
b. 71, 68, 79, 84, 78, 85, 69
c. 71
d. 71, 84
Answer:
71 ( C ).
Step-by-step explanation:
The impossible case is the third case i.e.71
because there is only one reading on the span gas hence it is impossible to carry out a t-test on just one valid reading in an experiment.
A signalized intersection has a cycle length of 70 seconds. For one traffic movement, the displayed all-red time is set to 2 seconds while the displayed yellow time is 5 seconds. The effective red time is 37 seconds and the total lost time per cycle for the movement is 4 seconds. What is the displayed green time for the traffic movement
Answer:
the displayed green time for the traffic movement is 30 seconds
Step-by-step explanation:
Given the data in the question;
Cycle length; C = 70 seconds
Displayed all-red time; AR = 2 seconds
Displayed yellow time; Y = 5 seconds
Effective red time; r = 37 seconds
total lost time per cycle; [tex]t_L[/tex] = 4 seconds
the displayed green time for the traffic movement; G = ?
First we determine the Effective green time ( g );
Effective red time; r = Cycle length; C - Effective green time ( g )
so,
Effective green time ( g ) = C - r
we substitute
Effective green time ( g ) = 70 seconds - 37 seconds
Effective green time ( g ) = 33 seconds
Now,
Effective green time ( g ) = displayed green time; G + Displayed yellow time; Y + Displayed all-red time; AR - total lost time per cycle; [tex]t_L[/tex]
i.e
g = G + Y + AR - [tex]t_L[/tex]
we substitute
33 = G + 5 + 2 - 4
33 = G + 3
G = 33 - 3
G = 30 seconds
Therefore, the displayed green time for the traffic movement is 30 seconds
PLEASE HELP WILL GIVE BRAINLIEST
WHAT IS DIVIDED BY 196
Answer:
1, 2, 4, 7, 14, 28, 49, 98, and 196.
Step-by-step explanation:
Find the circumstance: ?
A building code allows a maximum of 140 people in a meeting room. There is one large table in the room, along with some small tables. When filed, the large table seats 15 people, and the small table each seat 5 people. Which of the following can be used to find t, the greatest number of small tables that can be filled when the large tables are also filled?
Answer:
25 tables
Step-by-step explanation:
140-15=125
after the big table is filled 125 people are left
small tables fit 5 people
125÷5=25
1 big table and 25 small tables are needed to seat everyone
The Bransen Family picked 20 red apples, 28 yellow apples, and 12 bushel of green apples. Starting the following day, they ate 2 red apples and 3 yellow apples every day. When 6 red apples are left, how many yellow apples will be left?
9514 1404 393
Answer:
7
Step-by-step explanation:
The number of red apples (r) in terms of the number of days (d) is ...
r = 20 -2d
The number of yellow apples (y) in terms of the number of days (d) is ...
y = 28 -3d
Using the first equation to write and expression for d, we can substitute into the second equation.
r -20 = -2d
(20 -r)/2 = d . . . . from the first equation
Then ...
y = 28 -3(20 -r)/2 = 28 -30 +3/2r = (3/2)r -2
For 6 red apples left, the number of yellow apples left is ...
y = (3/2)(6) -2 = 7
7 yellow apples will be left when 6 red apples are left.
If you know how to solve this, Please answer it. Thank You
The first one to answer the question right, will get Brainlist!
I PROMISE!!!!!
Question 9
Two sides of a triangle have lengths 10 and 15.
What must be true about the length of the third side?
Greater than 5 but less than 25
Less than 15
Less than 25
Answer:
Two sides of a triangle have lengths 10 and 15.
What must be true about the length of the third side?
Greater than 5 but less than 25
Less than 15
Less than 25
Step-by-step explanation:
Eugene and Jenny are selling cookie dough for a school fundraiser. Customers can buy packages
of chocolate chip cookie dough and packages of gingerbread cookie dough. Eugene sold i
package of chocolate chip cookie dough and 10 packages of gingerbread cookie dough for a total
of $174. Jenny sold 4 packages of chocolate chip cookie dough and 2 packages of gingerbread
cookie dough for a total of $50. Find the cost each of one package of chocolate chip cookie
dough and one package of gingerbread cookie dough.
.
.
Two sides of a triangle have lengths 10 and 15.
What must be true about the length of the third side?
Greater than 5 but less than 25
Less than 15
Less than 25
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
If the function f(x)=Mx+b has an inverse function , which statement must be true
m≠0, m must not be zero. I hope this helps!
What are the domain and range of the function below? domain: (-40)
range: (-2,00)
domain: (-3,0)
range: [-2.00)
domain: (-0,00
range: -2.00)
domain: [-2.00)
range
CO
range{-2,00)
Step-by-step explanation:
In the graph the domain is {-3, -1, 0, 1, 2} and range is {-2, 1}
What is a function?A relation is a function if it has only One y-value for each x-value.
The domain and range are defined for a relation and they are the sets of all the x-coordinates and all the y-coordinates of ordered pairs respectively.
If the relation is, R = {(2, 1), (1, 1), (0, 1), (-1, -2), (-3, -2)}, then:
Domain = the set of all x-coordinates = {-3, -1, 0, 1, 2}
Range = the set of all y-coordinates = {-2, 1}
To learn more on Functions click:
https://brainly.com/question/30721594
#SPJ7
Randomly picking a green care from a standard deck of playing cards
A program evaluator wanted to know if a combination of experience and education gave leadership candidates an advantage in meeting job performance standards better than experience alone, or education alone. There were a total of 39 candidates who had both experience and education, and 200 candidates who had either experience or education. Of the candidates who had both experience and education, 21 met the standards, while 18 did not meet the standards. Of the candidates who had only experience or education, 100 met the standards, and 100 did not meet the standards.
Select the correct statistical test to determine if there is a relationship between preparation and meeting the standards, calculate the results, and communicate the results.
a. None of the choices are correct.
b. A Spearman rs is the best choice. The test reveals that there is a strong correlation between preparation and meeting the standards (rs = [237] = 1.00, p <.05). This means there is a relationship between the variables.
c. A chi-square test would be the best choice for examining observed data. The results are significant, (X- [1, N = 239] = 0.19, p<.05). This means that there was a relationship between preparation and meeting the standards, we reject the null hypothesis that the variables are independent.
d. A chi-square test would be the best choice for examining observed data. The results are not significant (X4 [1, N = 239] = 0.19, p > .05). This means that there was not a relationship between preparation and meeting the standards, we retain the null hypothesis that the variables are independent.
Answer:
pol
Step-by-step explanation:
Three plants manufacture hard drives and ship them to a warehouse for distribution. Plant I produces 54% of the warehouses inventory with a 4% defect rate. Plant II produces 35% of the warehouses inventory with an 8% defect rate. Plant III produces the remainder of the warehouses inventory with a 12% defect rate. (a) (5 points) A warehouse inspector selects one hard drive at random. What is the probability that a randomly selected hard drive is defectiv
Answer:
A. 0.028
B. 0.0628
C. 0.45
Step-by-step explanation:
A. Calculation to determine the probability that it is adefective hard drive and from plant II
Using CONDITIONAL PROBABILITY formula
P(B∩A2) =P(A2)P(B|A2)
Let plug in the formula
P(B∩A2)= 0.35×0.08
P(B∩A2)= 0.028
Therefore the probability that it is adefective hard drive and from plant II will be 0.028
B. Calculation to determine the probability that a randomly selected hard drive is defective
Using LAW OF TOTAL PROBABILITY formula
P(B) =P(A1)P(B|A1) +P(A2)P(B|A2) +P(A3)P(B|A3)
Let plug in the formula
P(B)= 0.54×0.04 + 0.35×0.08 + 0.11×0.12
P(B)=0.0216+0.028+0.0132
P(B)= 0.0628
Therefore the probability that a randomly selected hard drive is defective is 0.0628
C. Calculation to determine the probability that it came from plant II
Using CONDITIONAL PROBABILITY formula two twice
P(A2|B) =P(A2∩B)/P(B)
Let plug in the formula
P(A2|B)=0.0280/0.0628
P(A2|B)= 0.45
Therefore the probability that it came from plant II is 0.45
3 A random sample of 100 PUJ (public utility jeep) shows that a jeepney is driven on the average 24,500 km per year, with a standard deviation of 3,900 kilometers a Construct a 99% confidence interval for the average number of km a jeepney is driven annually b. What can we assert with 99% confidence about the possible size of our error if we estimate the average number of km driven by jeepney drivers to be 23, 500kn per year
Answer:
Step-by-step explanation:
BESTIES PLEASE HELP ME
M drives past two traffic lights. Probability that both are red is .35 and probability that firest is red is .48. wht is probability that second light is red, given that first light is red?
Answer:
Step-by-step explanation:
Overall probability = Probability1 *Probability2
Using the data you already have, you can fill it in as
0.35 = 0.48 * P2
Rearrange to isolate P2, by dividing both sides by 0.48, so
0.35/0.48 = P2
P2 = 0.7291666..., which rounded to two d.p is 0.73
So d)0.73 is correct
at what rate will £420 yield
£70 in 4 years
Answer:
4.17%
Step-by-step explanation:
Rate = interest earned / (principal x time)
70 / (4 x 420) = = 0.0417 = 4.17%
Please look at the image
Answer:
STN = 65 Completing the 180 degrees
115+m(STN)=180
m(STN)=65
mNTR=115
because The NTR and MTS meet theyself
mRTM=65
same The NTR and MTS
because RTM ans STN meet theyself
hopefully you understand it
i am trying hard to explain the question when i solve it but my engilish is not helping to handle it
Which ordered pair is NOT a solution to the inequality in the graph? (5,1) (4,6) (0,0) (-2,-8)
====================================================
Explanation:
The red shaded region is the solution set. In other words, if the point is in the red region, then it is a solution. A point like (0,0) is in the red area, so we cross that off the list. The same applies for (4,6) and (-2,-8) as well.
In contrast, a point like (5,1) is not in the red shaded area, so this point is not a solution. Hence it's the final answer.
Note: the solid boundary line means points on the boundary are considered solutions. A dashed boundary line would be used to exclude boundary points from the solution set. Solid boundary lines always go with "or equal to".
Refer to the drawing below if you need a visual of what's going on. I've plotted the four points on the graph given.
--------------------------
Here's an algebraic approach if you don't have a graph and only have the inequality. Ignore this section if you prefer the first section above.
If we plugged (x,y) = (0,0) into the inequality, then we get...
[tex]y \ge 2x-4\\\\0 \ge 2(0)-4\\\\0 \ge 0-4\\\\0 \ge -4\\\\[/tex]
That's a true statement because 0 is to the right of -4 on the number line, making 0 larger than -4. Since the last inequality is true, this makes the first inequality true. Furthermore, it algebraically confirms why (0,0) is a solution. You should find that (4,6) and (-2,-8) will lead to true statements as well, so they are solutions.
In contrast, (x,y) = (5,1) is not a solution because...
[tex]y \ge 2x-4\\\\1 \ge 2(5)-4\\\\1 \ge 10-4\\\\1 \ge 6\\\\[/tex]
which is false. The value 1 is not larger than 6, nor is it equal to 6.
1800=3×N
help asap plzzz
36. Saudi Arabia has proven oil reserves of
2.63 x 1011 barrels. Kuwait has proven oil
reserves of 9.78 x 1010 barrels. Canada
has proven oil reserves of 1.789 x 1011
barrels. What are the combined proven
oil reserves of the three countries?
Answer:
5.397*10^11
Step-by-step explanation:
2.63*10^11
0.978*10^11
1.789*10^11
--------------
5.397*10^11
What is the LCD for the given equation? 1/v^2=1/3v-2/v^2
help pleaseeeeeeeeeeeeeeeeeeeeeeeee
Answer:
it is number 2 just read it with an open mind
Step-by-step explanation:
Jose starts with $250 and spends $25 a week. Martin starts with $30 and saves $30 a week. When do Jose and Martin have the
same amount of money? Use for time and for saving.
Answer:
250-25=225 week 1
200=week 2
175= week 3
150= week 4
Martin
60= week 1
90= week 2
120=week 3
150= week 4
Step-by-step explanation:
y is directly proportional to the positive square root of( x+2)² when x = 8 y= 250 find y when x = 4
Answer:
150
Step-by-step explanation:
Since y is directly proportional to sqrt((x+2)^2), there is a constant,k, such that
y=ksqrt((x+2)^2)
We are given a pair (x,y) in this relation. Let's plug in (8,250 ) to find k.
250=ksqrt((8+2)^2)
250=ksqrt((10)^2)
250=k10
250/10=k
25=k
So for any pair (x,y) we have the relation y=25((x+2)^2).
We are asked to find y when x=4.
y=25((4+2))^2
y=25(6)
y=150
Test to see if y is proportional to sqrt((x+2)^2)
For the given points: 250/150=10/6
The equation is true so we're great.
help!!!!!!!!!!!!!!!!!!!
Answer:
D. 1/5
Step-by-step explanation:
Because
0.2222...>0.2>0.12
26) Cary hiked 18 miles in 6 hours. If he continues at the same pace, how much farther can he hike in the next 2 hours?
27) Harry made 4 hits in 9 times at-bat. If she keeps the same success level, how many hits should she make in 18 times
at-bat?
28) In how many ways can 18 hikers be organized into 2 or more groups for trail clearing if all groups have the same number of hikers?
Mixed Review
Use the rules of divisibility to solve each problem below. Tell whether each number is divisible by 2, 3, 4, 5, 6, 9, or 10.
29) 12
30) 30
31) 360
32) 96
Answer:
same question
Step-by-step explanation:
After receiving a discount of 14.5% on its bulk order of toner cartridges, John's Office Supply pays $6,498.00. What was the price of the order before the discount?
?Answer:
Step-by-step explanation: