Answer:
68%
Step-by-step explanation:
The empirical rule basically states that 68% of the data falls within one standard deviation from the mean, 95% of the data falls within two standard deviations from the mean, and 99.7% of the data falls within three standard deviations from the mean.
So to find the percentage of IQ scores between 70 and 138, you need to find how far each of these numbers is from the mean in terms of the standard deviation.
If you subtract the standard deviation from the mean, you receive 87, and if you add the standard deviation to the mean, you receive 121.
This means that both of these numbers are within one standard deviation from the mean meaning according to the empirical rule, that means 68% of the IQ scores are between 70 and 138.
good luck, i hope this helps :)
Answer:
99.7%
Step-by-step explanation:
According to the empirical rule, approximately 99.7% of data values lie within 3 standard deviations of the mean.
If I add a -5 to both sides of an inequality, then the inequality symbol will change direction. True or False
Answer:
true
Step-by-step explanation:
What is the answer to 1014.16667 rounded to the nearest tenths
Suppose 88% of all batteries from a supplier have acceptable voltages. A certain type of flashlight requires two D batteries, and the flashlight will work only if both its batteries have acceptable voltages. Treat all batteries and flashlights as independent of one another. Suppose 20 randomly selected batteries are placed into 10 flashlights. What is the probability that at least 9 of the flashlights function properly
Answer:
0.3036 = 30.36% probability that at least 9 of the flashlights function properly.
Step-by-step explanation:
For each flashlight, there are only two possible outcomes. Either it works, or it does not. Flashlights are independent. This means that we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
Flashlight works correctly if both its batteries have acceptable voltages:
Each battery has an 88% = 0.88 probability of working correctly(having acceptable voltage), so the probability of the flashlight working correctly is given by:
[tex]p = (0.88)^2 = 0.7744[/tex]
10 flashlights.
This means that [tex]n = 10[/tex]
What is the probability that at least 9 of the flashlights function properly?
This is
[tex]P(X \geq 9) = P(X = 9) + P(X = 10)[/tex]
In which
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 9) = C_{10,9}(0.7744)^{9}.(0.2256)^{1} = 0.2260[/tex]
[tex]P(X = 10) = C_{10,10}(0.7744)^{10}.(0.2256)^{0} = 0.0776[/tex]
[tex]P(X \geq 9) = P(X = 9) + P(X = 10) = 0.2260 + 0.0776 = 0.3036[/tex]
0.3036 = 30.36% probability that at least 9 of the flashlights function properly.
Which expression is equivalent to -8 + 7.25 – 6 + 0.5?
A. 7.25 +0.5 - (8 - 6)
B. -(8 + 6) + (7.25 +0.5)
C.-13 + 7.75
D. -14 - 7.25
Where can you find the hypotenuse of a right triangle
Answer:
In geometry, a hypotenuse is the longest side of a right-angled triangle, the side opposite the right angle.
Step-by-step explanation:
Answer:
Opposite to the 90 degree angle.
Step-by-step explanation:
the hypotenuse is always the longest side with right triangles its always opposite of the right angle
Whats your zodiac sign?
Answer:
cancer the worst
Step-by-step explanation:
Find the least common
multiple of 12 and 48.
144
48
32
96
Help
Answer:
Step-by-step explanation:
48
Aniyah has 10 1/3 feet of ribbon. She wants to cut the ribbon into 1 2/5 size pieces. How many full pieces of ribbon can she cut? helpppp
Answer:
7
Step-by-step explanation:
Because 10 1/3 divided by 1 2/5 would be 7 and something and the question is asking how many full pieces, so just 7
when multiplying or dividing by a negative coefficient, you must flip the sign.
•True
or
•False
Answer:
I think the answer is True!
Step-by-step explanation:
Hope this helps
Answer:
true
Step-by-step explanation:
a negative times a negative is a positive same with dividing a negative by a negative
a positive times a negative is also negative
Are 5x²y and 5y^2x LIKE TERMS or NOT LIKE TERMS?
What is the answer to
-5 +2y = 9
y = 7x ?
Answer:
x = 1
y = 7
Step-by-step explanation:
Two equations, two unknowns. We know that y = 7x so we can substitute that into the first equation to get:
[tex]-5+2\left(7x\right)=9[/tex]
[tex]-5+14x=9[/tex]
[tex]14x=14[/tex]
This gives us x = 1.
Now plug this bag into either equation to find y, I will use the second since it's easier:
y = 7(1) = 7
what are the 3 points
Answer:
(0,-2) (3,-4) (6,-6)
Step-by-step explanation:
I think you start at (0,-2) then go over 3 to the right and down 2 since it's negative each time
A sample of 25 PCC studentsspent an average of $75 with a standard deviation of $17.50. Another sample of 20 ELAC studentsshowed that they spent an average of $89 with a standard deviation of $14.40. Assume that the amounts by all PCCand all ELAC students are normally distributed with equal but unknown population standard deviations.
Required:
Using 5% significance level and a formal hypothesis test can you conclude that the mean amount spent by all PCC students is less than the mean spent by all ELAC students?
Answer:
Step-by-step explanation:
Given that:
For PCC
The sample size [tex]n_1[/tex] = 25
sample mean [tex]\overline x_1[/tex] = 75
standard deviation [tex]s_1[/tex] = 17.50
For ELAC
The sample size [tex]n_2[/tex] = 20
Sample mean [tex]\overline x_2 = 89[/tex]
Standard deviation [tex]s_2[/tex] = 14.40
Significance level = 0.05
The null hypothesis:
[tex]H_o : \mu_1 =\mu_2[/tex]
The alternative hypothesis;
[tex]H_1 : \mu_1< \mu_2[/tex]
Since the population standard deviation are synonymous pooled standard deviation; Then:
[tex]sp = \sqrt {\dfrac {(n_1-1)s_1^2)+(n_2-1)s_2^2 }{n_1+n_2-2}[/tex]
[tex]sp = \sqrt {\dfrac {(25-1)17.50^2)+(20-1)14.40^2 }{25+20-2}[/tex]
[tex]sp = 16.20[/tex]
The test statistics can be computed as:
[tex]t = \dfrac{\overline x_1 -\overline x_2}{sp \times \sqrt{\dfrac{1}{n_1} + \dfrac{1}{n_2} }}[/tex]
[tex]t = \dfrac{75-89}{16.20 \times \sqrt{\dfrac{1}{25} + \dfrac{1}{20} }}[/tex]
[tex]t = -2.88[/tex]
The p-value [tex]= P(t_{n_1+n_2-1} <t)[/tex]
[tex]= P(t_{43} <-2.88)[/tex]
= 0.0031
Decision Rule: To reject the null hypothesis if the p-value is less than the significance level
Conclusion: There is sufficient evidence to conclude that the mean amount spent by all PCC students is less than the mean amount spent by all ELAC students.
72/120 simplified help help help
Answer:
3/5
you get this by dividing 24 to both sides of 72/120
1. A wagon wheel has a radius of 4.9 inches. Which of the following is closest to the distance the wagon
travels in two turns of the wheel?
A 31 inches
B 15 inches
C 62 inches
D 75 inches
Answer:
b.
Step-by-step explanation:
can anyone help me with this please
Answer:
n+6
Step-by-step explanation:
Chang is 6 inches taller then Nancy so you must add 6 inches to Nancy's height to figure out Chang's height.
Answer:
it's n+6
Step-by-step explanation:
nancys height is unknown so n is the variable and Chang is 6 inches taller so you add Nancy's height plus 6
what is the solution to the equation x^2=64
Answer: Positive and negative 8
Step-by-step explanation:
Take the square root on both sides
[tex]\sqrt{x^2} =\sqrt{64}[/tex]
x = ±8
Answer:
x = - 8, x = 8
Step-by-step explanation:
[tex] {x}^{2} = 64 \\ \\ x = \pm \sqrt{64} \\ \\ x = \pm8 \\ \\ x = - 8, \: \: x = 8[/tex]
Subtract -13xy from -5xy so
-5xy -(-13xy)=?
Answer:
8xy
Step-by-step explanation:
Subtract -13xy from -5xy
-5xy - (-13xy) =
-5xy + 13xy =
8xy
good luck, i hope this helps:)
PLSSS HELP AND SHOW WORK PLEASE!
*Ms.Wilson ate 1/4 of a pizza in 12 minutes.*
1. If the pizza has 8 slices, how many slices will she eat in 18 minutes?
2. What fraction of the pizza will she eat in 30 minutes?
Problem 1
Answer: 3 slices-------------------------------------
Explanation:
1/4 = 0.25
She eats 25% of a pizza in 12 minutes
We can form the ratio 0.25/12
This ratio is then set equal to x/18. The value of x represents what proportion of the pizza is eaten after 18 minutes.
Solve for x
0.25/12 = x/18
0.25*18 = 12x ..... cross multiply
4.5 = 12x
12x = 4.5
x = 4.5/12
x = 0.375
x = 375/1000
x = (125*3)/(125*8)
x = 3/8
She ate 3/8 of the whole pizza in 18 minutes.
There are 8 slices in a full pizza, so (3/8)*8 = 3 means that she ate 3 slices.
Or you could say "eating 3 slices out of 8 total means she ate 3/8 of the full pizza".
===================================================
Problem 2
Answer: 5/8-------------------------------------
Explanation:
We'll use the same idea as before. Though now we're setting 0.25/12 equal to x/30
Solving for x leads to...
0.25/12 = x/30
0.25*30 = 12x
7.5 = 12x
12x = 7.5
x = 7.5/12
x = 0.625
x = 625/1000
x = (125*5)/(125*8)
x = 5/8
She will eat 5/8 of the pizza in 30 minutes.
Which is true about ballistic stretching exercises?
Answer:
its too donk
Step-by-step explanation:
alright ill go open up the shades
5. Which of the following is a pair of alternate exterior angles?
Angles 1 and 4
Angles 2 and 8
Angles 1 and 7
Angles 4 and 7
Answer: angle 1 and 7
Step-by-step explanation: you just do it
What is the ansar to 2+2 please I’m 3 and I hove preK hamewark
Answer:
4
Step-by-step explanation:
2+2=4
Simplify by dividing (-3/8) -5/9
Answer:
[tex]\frac{-27}{40}[/tex]
Step-by-step explanation:
[tex](\frac{-3}{8})[/tex]÷[tex]\frac{5}{9}[/tex]
[tex]\frac{-3}{8}[/tex]×[tex]\frac{9}{5}[/tex]
[tex]\frac{-27}{40}[/tex]
I need help fast find the answer
Answer:
22
Step-by-step explanation:
Which number in the expression is the CONSTANT?
бу — 5
Tourism is extremely important to the economy of Florida. Hotel occupancy is an often-reported measure of visitor volume and visitor activity (Orlando Sentinel). Hotel occupancy data for February in two consecutive years are as follows.
Current Year Previous Year
Occupied Rooms 1,470 1,440
Total Rooms 1,750 1,800
Required:
a. Formulate the hypothesis test that can be used to determine if there has been an increase in the proportion of rooms occupied over the one-year period. (Let p1 = population proportion of rooms occupied for current year and p2 = population proportion of rooms occupied for previous year.)
b. What is the estimated proportion of hotel rooms occupied each year?
c. Calculate the test statistic.
Answer:
Step-by-step explanation:
The null hypothesis and alternative hypothesis can be formulated as:
[tex]\mathbf{H_o: P_1 - P_2 \le 0}[/tex]
[tex]\mathbf{H_1 : P_1 -P_2> 0}[/tex]
From the information given:
The sample proportion of rooms occupied for the current year.
[tex]P_1 = \dfrac{1470}{1750}[/tex]
[tex]P_1 = 0.84[/tex]
Sample size [tex]n_1[/tex] = 1750 (total number of rooms for the current year)
The sample proportion of rooms occupied for the previous year.
[tex]P_2 = \dfrac{1440}{1800}[/tex]
[tex]P_2 =0.8[/tex]
Sample size [tex]n_2[/tex] = 1800 (total number of rooms for the previous year)
Thus, the estimated proportion of the hotel rooms occupied each year are:
Current Previous
0.84 0.80
Since this is a one-sided right-tailed test;
The pooled proportion can be computed as:
[tex]\hat p= \dfrac{p_1 \times n_1 + p_2 \times n_2}{n_1 + n_2}[/tex]
[tex]\hat p= \dfrac{0.84 \times 1750 + 0.80 \times1800}{1750 +1800}[/tex]
[tex]\hat p=0.8197[/tex]
The standard error SE = [tex]\sqrt{\hat p ( 1- \hat p) ( \dfrac{1}{n_1} + \dfrac{1}{n_2} )}[/tex]
[tex]= \sqrt{0.8197 ( 1-0.8197) ( \dfrac{1}{1750} + \dfrac{1}{1800} )}[/tex]
[tex]= \sqrt{0.8197 ( 0.1803) (0.00112698 )}[/tex]
[tex]=0.0129[/tex]
Finally, the test statistics is calculated as:
[tex]Z_{calc} = \dfrac{(0.84 - 0.8)}{0.0129}[/tex]
[tex]Z_{calc} = 3.101[/tex]
Find the length of the third side of a triangle, given the legs are 12in. and 36 in
Answer:
37.94
Step-by-step explanation:
not sure if this is what you need but if you use Pythagoras therom you should get there
a^2 + b^2= c^2
12^2+36^2=c^2
12^2+36^2= 1440
the square root of 1440 is 37.9433192
The point G(6,4) is rotated 180° clockwise around the origin. What
are the coordinates of the resulting point, G'?
Answer:
Step-by-step explanation:
when (x,y) is rotated through 180 then new coordinates are (-x',-y')
G(6,4)→G'(-6,-4)
2 5/8 divided by 3/7
Answer:
Answer is 6.125
Step-by-step explanation:
I hope it's helpful!
need help plssssssssssssssssssssssssssssssss
Answer:
29
Step-by-step explanation:
PEMDAS
PARENTHESIS: [3-10]=7
EXPONENTS: 3^3= 27
MULTIPLICATION:8×7=56
DIVISION:NONE
ADDITION:NONE
SUBTRACTING: 56-27=29
ANSWER: 29