Answer:
the population means are known the population variances are assumed equal but unknown
Step-by-step explanation:
If σ1= σ2 (= σ) but unknown , then the biased pooled or combined estimate of the common variance σ² ( the term common variance means that each population has the same variance ) is given by
Sp²= (n1-1) s1² + (n2-1) s2²/ n1+ n2- 2
So first assumption is correct.
When the population variances are assumed unequal and unknown
If σ1 ≠ σ2 but unknown
we use the sample estimates s1 and s2 to compute the standard error of the difference between the means.
S(x1`- x2`) = √s1²/ n1 + s2²/n2
So this is does not apply here.
pleasee fast help me pleaseeeeeeeeee
In a class, one third of the students like badminton, three-fourth of the students like football, 5 out of 6 of
the students like volleyball, 60 like football and volleyball, 65 like volleyball and badminton,
17 like badminton and football, 20% of the students like all three games and 8 students don't like any
game. Draw a Venn-diagram and find the total number of students in the class.
Answer:
The answer is below
Step-by-step explanation:
Let B represent those that like badminton, F represent those that like football and V represent those that like volleyball. Let x represent the total number of people.
n(B) = (1/3)x, n(F) = (3/4)x, n(V) = (5/6)x
n(B∩F∩V) = 20% of x = 0.2x
n(B∩F) = 17, hence n(B∩F∩V') = 17 - 0.2x
n(V∩F) = 60, hence n(B'∩F∩V) = 60 - 0.2x
n(B∩V) = 65, hence n(B∩F'∩V) = 65 - 0.2x
n(B∪F∪V)' = 8
n(B∩F'∩V') = (1/3)x - 0.2x - (17 - 0.2x) - (65 - 0.2x) = 0.533x - 82
n(B'∩F∩V') = (3/4)x - 0.2x - (17 - 0.2x) - (60 - 0.2x) = 0.95x - 77
n(B'∩F'∩V) = (5/6)x - 0.2x - (60 - 0.2x) - (65 - 0.2x) = 1.033x - 125
Therefore:
x = n(B∩F'∩V') + n(B'∩F∩V') + n(B'∩F'∩V) + n(B∩F∩V) + n(B∩F∩V') + n(B'∩F∩V) + n(B∩F'∩V) + n(B∪F∪V)'
x = (0.533x - 82) + (0.95x - 77) + (1.033x - 125) + (0.2x) + (17 - 0.2x) + (60 - 0.2x) + (65 - 0.2x) + 8
x = 2.1166x - 134
1.1166x = 134
x = 120
Therefore there was 120 students
find the value of x help ASAP
3x - 6 = 90
3x - 6 + 6 90 + 6
3x = 96
3x ÷ 3 = 96 ÷ 3
x = 32
seth put $500 in his savings account, which earns a earns a simple interest rate of 4%
A. use the simple interest equation ( I=Prt ) to find out how much interest seth earns after 6 years.
B. now find out how much interest seth wold earn if he were to earn 7% compound interest for 6 years
Someone help me out :)
Answer: sorry i dont know this
Step-by-step explanation:
Mr Sharma packed 42 kg of tea into one big bag and 6 small ones each of the same size the big bag contained 3/7 of the tea how many kg of tea did each small bag contain
Answer:
4kg
Step-by-step explanation:
Mr Sharma packed 42 kg of tea into one big bag and sox small bags each of the same size
The first step is to calculate the quantity in the big bag
= 3/7 × 42
= 3×6
= 18
The amount left in the remaining bags is
= 42-18
= 24
Therefore the kg of tea in the small bags can be calculated as follows
= 24/6
= 4
Hence there are 4kg of tea in the small bags
4. Does the following Infinite geometric series diverge or converge? Explain.
3 + 9 + 27 +81 +
It diverges; it does not have a sum.
It converges; It has a sum.
It diverges; it has a sum.
It converges; it does not have a sum.
Answer:
It diverges; it does not have a sum.
Step-by-step explanation:
3, 9, 27, 81, ..
ratio = r = 9/3 = 3
since |r| ≥ 1, it diverges and doesn't have a sum
The solution is, the given series is divergent and it has a sum infinity.
Option (A) is CORRECT. i.e. It diverges; it does not have a sum.
What is geometric series?A geometric series is a series in which the division of any consecutive two terms will be the same.
here, we have,
We are given to check whether the following infinite geometric series diverge or converge :
given that,
3 + 9 + 27 +81 +....
We know that
an infinite geometric series diverges if the modulus of the common ratio is greater than 1.
For the given geometric series, the common ratio r is given by
r = 9/3
= 3
So, we get
r = 3 > 1
Therefore, the given infinite geometric series diverges.
Also, we know that the sum of a divergent infinite geometric series with first term a and common ratio r is given by,
the sum will be infinity.
For the given series,
it does not have a sum.
Therefore, the required sum will be infinity.
Thus, the given series is divergent and it has a sum infinity.
Option (A) is CORRECT. i.e. It diverges; it does not have a sum.
For more about geometric series
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Find the volume of this sphere.
Use 3 for 7T
V [?]ft3
V = Tr3
1
3ft
PLEASE HELP
Answer:
eyjssghafhfa
th
at
hatt
hatthwwtu
twh
wth
tw
h
wth
th
wy
wty
wth
wth
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had to be 20 characters long...
I really need help !!!
Answer:
heyy sorry i dont really know what is the 'standard deviation' but as for the mean you go to add all the numebers together and divide them by the amount of numbers there are (7 in this scenario)
Step-by-step explanation:
21 + 29.5 + 38 + 46.5 + 55 + 63.5 + 72 = 325.5
then you divide 325.5 by the number of numbers present in the question
325.5 / 7 = 46.5
hope it helped :)
A right triangle has legs E and f and hypotenuse H. The value of e= 10. The angle opposite leg f is 35°. Which expression can be used to find the length of the hypotenuse? Show your work am offering brainliest and 45 points‼️‼️‼️
Answer:
sorry buddy i dont know the answer hope this helps
Step-by-step explanation:
Isn't this what u did to me when i needed help and took my points away.
A rectangle is to be drawn with perimeter 64cm. If the length is to be 14cm more than the width, determine the are of the rectangle.
Please use system of linear equations by elimination OR substitution. I need the work as well please.
P = 64 cm
2(( x + 14) + x) = 64
2x + 28 + 2x = 64
4x + 28 = 64
4x = 64 - 28
4x = 36
x = 36/4
x = 4
width = 4
lenight = 18
area = l x b
area = 18 x 4
area = 72
Which equation represents a line which is parallel to the line 3x+y=8?
A. y=3x-4
B. y=−3x+2
C. y= 1/3x + 6
D. y= -1/3x-2
Answer:its A or C
Step-by-step explanation:i hope this helps
A 70-year-old male pays 79.79 per month for his term life policy 180-year-old pays 349.30 per month. What is the percent of increase in premium costs from age 70 to 80?
Answer: [tex]337.77\%[/tex]
Step-by-step explanation:
Given
For 70 year old, premium is 79.79 per month
For 80 year old it is 349.30 per month
Percentage increase in premium costs from age 70 to 80 is
[tex]\Rightarrow \%\ \text{increase}=\dfrac{349.30-79.79}{9.79}\times 100\\\\\Rightarrow \%\ \text{increase}=\dfrac{269.51}{79.79}\times 100\\\\\Rightarrow \%\ \text{increase}=337.77\%[/tex]
HELLLLPPPPPPP PLEASEEEEEE BEGGGGI G SOMEONE PLEASEEEEEEEEE
Answer:113
Step-by-step explanation:
Find an ordered pair that represents the vector from (-3.7,2) to (-4, -5).
a.
(-7.7,-3)
c.
(1.3,7)
b.
(-0.3,-7)
d.
(7.7,3)
Please select the best answer from the choices provided
A
B
C
D
Given:
A vector from (-3.7,2) to (-4, -5).
To find:
An ordered pair that represents the vector
Solution:
If [tex](x_1,y_1)[/tex] is the initial point and [tex](x_2,y_2)[/tex] is the terminal point of a vector, then ordered pair that represents the vector is:
[tex](x_2-x_1,y_2-y_1)[/tex]
A vector from (-3.7,2) to (-4, -5). So, the ordered pair that represents the vector is:
[tex](x_2-x_1,y_2-y_1)=(-4-(-3.7),-5-2)[/tex]
[tex](x_2-x_1,y_2-y_1)=(-4+3.7,-7)[/tex]
[tex](x_2-x_1,y_2-y_1)=(-0.3,-7)[/tex]
Therefore, the correct option is b, i.e., (-0.3,-7).
Find the equation of a line with m = 3 that passes though the point (-12,
4).
Answer:
y = 3x + 40
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
Here m = 3 , then
y = 3x + c ← is the partial equation
To find c substitute (- 12, 4 ) into the partial equation
4 = - 36 + c ⇒ c = 4 + 36 = 40
y = 3x + 40 ← equation of line
find the value of x.
[tex]\huge\bold{To\:find:}[/tex]
✎ The value of [tex]x[/tex].
[tex]\large\mathfrak{{\pmb{\underline{\orange{Solution}}{\orange{:}}}}}[/tex]
[tex]\sf\purple{The\:value\:of\:x\:is\:10°. }[/tex]
[tex]\large\mathfrak{{\pmb{\underline{\red{Step-by-step\:explanation}}{\orange{:}}}}}[/tex]
Since it is right angle,
[tex]Sum \: of \: angles \: = 90° \\ ⇢ 2x °+ 7x° =90 ° \\ ⇢9x° = 90° \\ ⇢x° = \frac{90°}{9} \\ ⇢x° = 10°[/tex]
[tex]\sf\blue{Therefore,\:the\:value\:of\:x\:is\:10°.}[/tex]
[tex]\huge\bold{To\:verify :}[/tex]
[tex]2x° + 7x° = 90° \\ ➡ \: 2 \times 10° +7 \times 10° = 90° \\ ➡ \: 20° + 70° = 90° \\ ➡ \: 90° = 90° \\ ➡ \: L.H.S.=R. H. S[/tex]
Hence verified.
[tex]\circ \: \: { \underline{ \boxed{ \sf{ \color{green}{Happy\:learning.ඞ}}}}}∘[/tex]
A coffee shop sells five different flavors of coffee. They want to compare how much of each is sold on Saturday morning. Which graph would be the best?
a) bar graph
b) histogram
c) line graph
d) scatter plot
Answer:
Bar graph
Step-by-step explanation:
is the right answer for mine
A florist used 14 flowers to make a bouquet including 6 daisies what is the probability that a randomly selected flower will be a daisy
Answer:
3/7(when simplified)
Step-by-step explanation:
there are 6 daisies out of 14 flowers and so the probability would be 6/14. When simplified, the answer would be 3/7
Here is a equation. Find x.
(2+x)5=11
Answer:
x = 0.2
Step-by-step explanation:
Distribute the 5 to (2 + x) to make it 10 + 5x = 11. You can rewrite it to make it 5x + 10 = 11 to make it easier if you want but you dont have to. Subtract the ten from both sides to make it 5x = 1. Divide both sides by 5 to get 0.2. If you want to double check your answer you can substitute 0.2 in for x in (2 + x)5 = 11 or in 5x + 10 = 11. It doesn't matter which.
Pranav paints a wall of area 53m^2 one litre of paint covers an area of 4.5m^2 paint is sold in 2.5 litre tins, each costing $24.75 Pranav buys the least number of tins to paint this wall work out the cost of the paint
Answer:
The cost of the paint will be $123.75.
Step-by-step explanation:
Since Pranav paints a wall of area 53m ^ 2, and one liter of paint covers an area of 4.5m ^ 2, and paint is sold in 2.5 liter tins, each costing $ 24.75, if Pranav buys the least number of tins to paint this wall, to determine the cost of the paint, the following calculation must be performed:
(53 / 4.5) = liters of paint needed
11.77 = liters of paint needed
11.77 / 2.5 = tins of paint needed
4.71 = tins of paint needed (rounds to 5)
5 x 24.75 = Total cost
123.75 = Total cost
The cost of the paint will be $123.75.
A certain coin is a circle with diameter 18 mm. What is the exact area of either face of the coin?
The exact area of either face of the coin is mm2.
(Simplify your answer. Type an exact answer in terms of st.)
============================================================
Explanation:
If the diameter is d = 18, then the radius is half that at r = d/2 = 18/2 = 9
Then that radius is plugged into the circle area formula below
A = pi*r^2
A = pi*9^2
A = pi*81
A = 81pi
If you were to use an approximation like pi = 3.14, then the approximate area would be 81*pi = 81*3.14 = 254.34 mm^2; however, your teacher wants you to write the exact area.
John is 27 years old. His brother James is 15
years old. What is the ratio of John's age to
his brother's? A. 5:9 B.9:4 0.9:5
D.3:5 E. 5:3
Answer:
C. 9:5
Step-by-step explanation:
I got a 100 on my test
Determine the probability of three sunny days in a row when the probability of rain on each day is 20%
A) 80 %
B) 0.8%
C) 51.2%
D) 60 %
The probability of 3 sunny days in a row is P = 0.512, so the correct option is C.
How to find the probability?We know that the probability of rain each day is 20%. Then the probability of a sunny day is 100% - 20% = 80%.
Writing this probability in the decimal form we get 0.8.
Now, to get 3 sunny days in a row, we need to have the probability 0.8 3 times (and remember that the probabilities multiply between them) so the joint probability is:
[tex]P = (0.8)^3 = 0.512[/tex]
To get it in percentage form, we multiply it by 100%.
P = 0.512*100% = 51.2%
So the correct option is C.
If you want to learn more about probability:
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Which transformation will always map a parallelogram onto itself?
OA
a 90° rotation about its center
B.
a reflection across one of its diagonals
Ос.
a 180° rotation about its center
OD.
a reflection across a line jolning the midpoints of opposite sides
Explanation:
Draw out a rectangle and make sure it's not a square. So you could have it be longer than it is tall. Imagine rotating that rectangle 180 degrees. The before and after (preimage and image) will be identical. The same applies if we slanted the sides of this rectangle. This shows that any parallelogram has rotational symmetry.
Side note: any rectangle is a parallelogram, but not the other way around.
pleaseeeee helppppp!!!!! I have to turn this in...!!!
PLS HELP ASAP ITS DUE IN 2HR PLS
Answer:
From 10 a.m. to 2 p.m., the temperature at Sam's house increased by 8 degrees Fahrenheit.
Step-by-step explanation:
Write as a number equation ----> 2 - (-6) = 8
I have a question what is 3/4 × 4/5?
Answer:
3/5
Step-by-step explanation:
Because if you take 3/4 x 4/5 you can cross simplify the 4's in the equation and they cancel eachother out, so then u are left off with 3/1 x 1/5 and then you get 3/5
need help in this question
Answer:
B) 9
Step-by-step explanation:
110 + 75 + 11x - 9 + 8x + 13 = 360
19x + 189 = 360
19x (+ 189 - 189) = 360 - 189
19x = 171
19x/19 = 171/19
x = 9
Which expression is equivalent to 83 x 52?
A 5(80 x 3)
B. 5x (80+3)
C. 80 (3x5)
D. 80 x (3+5)
Are you sure about the numbers ( 83 x 52) ? I think there is a mistake
Which could be a graph which represents a quadratic that is a perfect square trinomial?
Answer:
D/#4 represents a quadratic that is a perfect square trinominal. :-D
2/3+1/4=
Pls help meeeeeeee
Answer:
11/12 should be the correct answer!
Step-by-step explanation:
Let's make the denominator the same!
Lcm of 3 and 4 is 12
sooo... multiply
2/3 x 4/4 = 8/12
1/4 x 3/3 = 3/12
8/12 + 3/12 = 11/12