A half-century ago, the mean height of women in a particular country in their 20s was inches. Assume that the heights of today's women in their 20s are approximately normally distributed with a standard deviation of inches. If the mean height today is the same as that of a half-century ago, what percentage of all samples of of today's women in their 20s have mean heights of at least inches?
Answer:
0.26684
Step-by-step explanation:
Given that :
Mean, μ = 62.5
Standard deviation, σ = 1.96
P(Z ≥ 63.72)
The Zscore = (x - μ) / σ
P(Z ≥ (x - μ) / σ)
P(Z ≥ (63.72 - 62.5) / 1. 96) = P(Z ≥ 0.6224)
P(Z ≥ 0.6224) = 1 - P(Z < 0.6224)
1 - P(Z < 0.6224) = 1 - 0.73316 = 0.26684
1. In 2020, the populations of City A and City B were equal. From 2015 to 2020, the population of City A increased by 20% and the population of City B decreased by 10%. If the population of City A was 120,000 in 2015, what is the population of City B in 2015?
2. A chef is preparing a sauce for a steak she offers as a key dish in her menu. To prepare the sauce she needs to prepare a mix with 40% butter, with the rest being egg yolk. In the kitchen right now, she only has a sauce that has 20% butter (rest is egg yolk) and a sauce that has 50% butter (rest is egg yolk) in stock. In what ratio should she mix the 20% sauce with the 50% sauce in order to obtain the 40% sauce that she needs to prepare her famous recipe?
3. A book was on sale for 30% off its original price. If the sale price of the book was $28, what was the original price of the book? (Assuming there is no sales tax)
4. At a retail store, they needed to do surveys of 32 stores which equals 40% of all their stores. How many stores does the retailer have in total?*
Answer:
180000 people
1 : 2
$40
80 stores
Step-by-step explanation:
1.)
Population in 2020 are equal : Let population =
City A increased by 20% From 120,000 in 2015
(1 + 0.2) * 120,000 = (1.2 * 120,000) = 144,000
Hence, city A = 144,000.
Since, city A and B have equal population ; city B also has a population of 144000 in 2020.
Let population in 2015 = x
(1 - 0.2) * x = 144000
0.8x = 144000
x = 144000/0.8
x = 180,000
2.)
Let proportion of 20% butter = x and proportion of 50% butter = 1 - x
0.2x + 0.5(1 - x) = 0.4
0.2x + 0.5 - 0.5x = 0.4
-0.3x + 0.5 = 0.4
-0.3x = 0.4 - 0.5
-0.3x = - 0.1
x = 0.1/0.3
x = 0.3333
(1-x) = 1 - 0.33333 = 0.6666%
0.3333% of 20% butter
0.6666% of 50% butter
Hence ;
0.3333 : 0.6666
1 : 2
3.)
Let original price of book = x
Discount on sale = 30%
Sale price = $28
Sale price = original price * (1 - discount)
$28 = (1 - 0.3) * x
$28 = 0.7x
x = $28/0.7
x = $40
4.)
Let total number of stores = x
Store surveys needed = 32
40% of total stores = 32 stores
0.4x = 32
x = 32 / 0.4
x = 80
answer this question
Answer:
(-2, 13) (-1,8) (0, 5) (1, 4) (2, 5) (3, 8)
(2.4 , 6) or (-0.4, 6)
Step-by-step explanation:
Graph y = 6 on top of y = [tex]x^{2}[/tex] -2x + 5 and use the points where the two lines meet.
Peter, Jan, and Maxim are classmates. Their total score for the last test was 269. Peter's score was more than the sum of Jan's and Maxim's scores. What could be Peter's least possible score?
Answer:
135
Step-by-step explanation:
Given that :
Total score obtained by Peter, Jan and Maxim = 269
Let :
Peter's score = x
Jan's score = y
Maxim's score = z
x + y + z = 269
x > (y + z)
For x to be greater Than y + z ;
Then x > (269 / 2) ; x > 134.5
The least possible x score is 135
Hence, Peter's least possible score is 135.
Find x and explain how you found x
Answer:
x=60
Step-by-step explanation:
There are different ways to find x but this is what I found easiest.
To solve first note that AOD and CFB are vertical angles; this means that they are congruent. AOD consists of two angles with the measurements of 90 and x. CFB consists of two angles with the measurements of 30 and 2x. So, to find x set add the adjacent angles and set them equal to the other pair of angles. The equation would be [tex]90+x=30+2x[/tex]. First, subtract x from both sides; this makes the equation [tex]90=30+x[/tex]. Then, subtract 30 from both sides. This gives the final answer, x=60.
Which equation could represent a linear combination of the systems?
9514 1404 393
Answer:
(b) 0 = -78
Step-by-step explanation:
Subtracting 6 times the first equation from the second will give ...
(4x +15y) -6(2/3x +5/2y) = (12) -6(15)
0 = -78
Answer:
the answer is b
Step-by-step explanation:
Any help would be very appreciated
Answer:
21
Step-by-step explanation:
Since this is a right triangle, we can use trig functions
tan theta = opp/ adj
tan 60 = x / 7 sqrt(3)
7 sqrt(3) tan 60 = x
7 sqrt(3) sqrt(3) = x
7*3 = x
21 = x
Use differentials to approximate the change in cost corresponding to an increase in sales (or production) of one unit. Then compare this with the actual change in cost.
Function x-Value
C=0.025x^2 + 3x + 4 x=10
dC= ___________
ΔC= __________
Answer:
dC=3.5
DC is between 3.475 and 3.525
Step-by-step explanation:
So let dx=1 since the change there is a change in 1 unit.
Find dC/dx by differentiating the expression named C.
dC/dx=0.05x+3
So dC=(0.05x+3) dx
Plug in x=10 and dx=1:
dC=(0.05×10+3)(1)
dC=(0.5+3)
dC=3.5
Let D be the change in cost-the triangle thing.
Since dx=1 we only want the change in unit to be within 1 in difference.
So this means we want it to be from x=9 to x=1] ot from x=10 to x=11.
Let's do from x=9 to x=10 first:
DC=C(10)-C(9)
DC=[0.025×10^2+3×10+4]-[0.025×9^2+3×9+4]
DC=[2.5+30+4]-[0.025×81+27+4]
DC=[36.5]-[2.025+31]
DC=[36.5]-[33.025]
DC=3.475
Now let's do from x=10 to x=11
DC=[0.025×11^2+3×11+4]-[0.025×10^2+3×10+4]
DC=[0.025×121+33+4]-[36.5]
DC=[3.025+37]-[36.5]
DC=[40.025]-[36.5]
DC=3.525
So DC, the change in cost where the change in unit is 1, is between 3.475 and 3.525.
A satellite orbits earth at a speed of 22100 feet per second (ft/s). Use the following facts to convert this speed to miles per hour (mph). 1 mile = 5280 ft 1 min = 60 sec 1 hour = 60 min
15,068 mi/hr
Step-by-step explanation:
[tex]22100\:\frac{\text{ft}}{\text{s}}×\frac{1\:\text{mi}}{5280\:\text{ft}}×\frac{60\:\text{s}}{1\:\text{min}}×\frac{60\:\text{min}}{1\:\text{hr}}[/tex]
[tex]=15,068\:\text{mi/hr}[/tex]
The speed of 22100 feet per second will be 15068.18 miles per hour.
What is unit conversion?Multiplication or division by a numerical factor, selection of the correct number of significant figures, and unit conversion are all steps in a multi-step procedure.
Unit conversion is the expression of the same property in a different unit of measurement. Time, for example, can be expressed in minutes rather than hours, and distance can be converted from miles to kilometres, feet, or any other length measurement.
Given that the speed of the satellite is 22100 feet per second. The speed in miles per hour will be calculated as,
22100 ft /s = ( 22100 x 3600 ) / 5280
22100 ft/s = 79560000 / 5280
22100 ft/s = 15068.18 miles per hour
To know more about unit conversion follow
https://brainly.com/question/28901160
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In this problem, y = 1/(1 + c1e−x) is a one-parameter family of solutions of the first-order DE y' = y − y2. Find a solution of the first-order IVP consisting of this differential equation and the given initial condition. y(0)=-1/3
If y (0) = -1/3, then
-1/3 = 1 / (1 + C e ⁻⁰)
Solve for C :
-1/3 = 1 / (1 + C )
-3 = 1 + C
C = -4
So the particular solution to the DE that satisfies the given initial condition is
[tex]\boxed{y=\dfrac1{1-4e^{-x}}}[/tex]
Find mBFE, help ASAP!!!
Answer: C
<BFE is 148 degrees
Step-by-step explanation:
We have angles <BFC (57 degrees) and <CFD (34 degrees), but what is <DFE?
1. The angle symbol in the vertexes shows that <BFC is congruent to <DFE, meaning that they are the same
2. Knowing this, we can safely say that <DFE is equal to 57 degrees because <BFC is also 57 degrees.
3. Now, we have all the angles we need to find out <BFE.
4. <BFC+<CFD+<DFE=<BFE
5. Substitute to get
57+34+57=<BFE
91+57=<BFE
148=<BFE
6. Now we know that the answer is 148 degrees.
X^2 + bx + 49 is a perfect squad trinomial what is one possible value of b? & I need help with the others also due soon!
20. (2) 14
A perfect square trinomial will factor into two expressions that are the same, for example: x^2 + 6x + 9 = (x + 3)(x + 3). Since this problem has a C value of 49, it will factor into (x + 7)(x + 7). 7 doubled is 14, therefore one possible value of B is 7.
21. (4) 2, -12
x^2 + 10x + 25 = 24 + 25
(x + 5)^2 = 49
x + 5 = +/- 7
x = 2, -12
22. (3) 3 + sqrt(17)
x^2 - 6x = 8
Complete the Square
x^2 - 6x + 9 = 8 + 9
(x - 3)^2 = 17
x - 3 = +/- sqrt(17)
x = 3 + sqrt(17), 3 - sqrt(17)
23. (1) 1, -5
x^2 + 4x - 5 = 0
x^2 + 4x = 5
x^2 + 4x + 4 = 5 + 4
(x + 2)^2 = 9
x + 2 = +/- 3
x = 1, -5
Hope this helps!
Riley wants to buy a car and has a choice between two different banks. One bank is offering a simple interest rate of 4.5% and the other bank is offering a rate of 4.5% compounded annually. Which is the better deal?
Does the point (0, 0) satisfy the equation y = x2?
Answer:
The point is a solution
Step-by-step explanation:
y = x^2
Substitute the point into the equation and see if it is true
0 = 0^2
0=0
True
Find the slope, if it exists, of the line containing the points (10,-3) and (10,-8).
Select the correct choice below and, if necessary, fill in the answer box to complete your choice.
m=
Answer:
The slope is undefined.
Step-by-step explanation:
The line must pass through the points (10,-3) and (10,-8), meaning that it must be vertical. The slope of a line is undefined if the line is vertical.
9. Which is a true statement about the denominator in a fraction?
(Select one answer)
It is always a negative number
It cannot be 0
It has to be an even number
It is always smaller than the numerator
Answer:
It cannot be 0
Step-by-step explanation:
it can also be positive number :2/4
it can be odd number too:3/9
it is bigger than numerator bcoz we have to divide it for numerator
So, 0 number cannot be put as denominator in fraction is true statement
PLEASE HELP AND BE CORRECT BEFORE ANSWERING PLEASE AND THANK YOU
9514 1404 393
Answer:
6 units
Step-by-step explanation:
The dilation factor is 2, so the length of A'B' will be 2 times the length of AB.
AB can be seen to be 3 units, so A'B' will be 2×3 = 6 units.
How
many solutions are there to the equation below?
4(x - 5) = 3x + 7
A. One solution
B. No solution
O C. Infinitely many solutions
SUB
Answer:
A one solution
Step-by-step explanation:
4(x - 5) = 3x + 7
Distribute
4x - 20 = 3x+7
Subtract 3x from each side
4x-3x-20 = 3x+7-3x
x -20 = 7
Add 20 to each side
x -20+20 = 7+20
x = 27
There is one solution
Answer:
Step-by-step explanation:
Let's simplify that before we make the decision, shall we? We'll get rid of the parenthesis by distribution and then combine like terms.
4x - 20 = 3x + 7 and combining like terms and getting everything on one side of the equals sign:
1x - 27 = 0. Since that x has a power of 1 on it (linear), that means we have only 1 solution. If that was an x², we would have 2 solutions; if that was an x³, we would have 3 solutions, etc.
What is the value of cot ø= 2/3 what is the value of csc ø
Answer:
Step-by-step explanation:
cotθ = cosθ/sinθ = 2/3
sinθ = 3/√(2²+3²) = 3/√13
cscθ = 1/sinθ = √13/3
This is a list of the heights ( each nearest cm ) of 12 children
150 134 136 139 131 141
132 134 136 137 150 146
Select the type of the data.
Discrete
Continuous
Categorical
Qualitative
choose one
NO FAKE ANSWERS
FIRST MARKED BRAINLIST
qualitative
Step-by-step explanation:
b cos the question is in quality format
Answer:
cutee!
SUP???
Hiii friend :]
cuteee~!
prettyyy
(12 1/3 * 2) + (10 3/4 * 2)
Answer:
[tex](12\frac{1}{3} *2)+(10\frac{3}{4} *2)\\\\=(\frac{12(3)+1}{3} *2)+(\frac{10(4)+3}{4} *2)\\\\=\frac{37*2}{3} +\frac{43*2}{4} \\\\=\frac{74}{3} +\frac{86}{4} \\\\=\frac{74(4)+86(3)}{3*4} \\\\=\frac{296+258}{12} \\\\=\frac{554}{12}[/tex]
Find the intersection of the parabola y=-2x^2-4x+2 and the line -6x+y=14
Answer:
(-2,2) and (-3,-4)
Step-by-step explanation:
by graphing the line and parabola, you should get this graph
The length of the base of a triangle is twice it’s height. If the area of the triangle is 441 square kilometers, find the height
Answer:
21 kilometers
Step-by-step explanation:
Let the height be [tex]x[/tex]. Then, the length of the base is [tex]2x[/tex]. The formula for the area is of the triangle is given by base*height/2. Therefore, the area of the triangle is equal to [tex]\frac{x \cdot 2x}{2} = x^2[/tex], which is in turn equal to 441. Since [tex]x[/tex] must be positive, then [tex]21^2=441[/tex], meaning that the height is [tex]21[/tex] kilometers.
7/9 - 2/3 and 2/3 - 1/6
Answer:
The answer is 1/9 and 1/2
To make concrete, the ratio of cement to sand is 1 : 3. If cement and sand are sold in bags of equal mass, how many bags of cement are required to make concrete using 15 bags of sand?
Answer:
5 bags of cement are required.
Step-by-step explanation:
Since to make concrete, the ratio of cement to sand is 1: 3, if cement and sand are sold in bags of equal mass, to determine how many bags of cement are required to make concrete using 15 bags of sand the following calculation must be done:
Cement = 1
Sand = 3
3 = 15
1 = X
15/3 = X
5 = X
Therefore, 5 bags of cement are required.
7/18 - 1/3 , 1/2 - 1/5 - 1/10 and 3 1/2 - 2 5/9 please help thank you
Answer:
Step-by-step explanation:
7/18=7/18
it cant be divided agian
1/3=1/3
it cant be divded agian
1/5=1/5
it cant be divded agian
1/10=1/10
it cant be divded agian
3 1/2=3/2
2 5/9 =10/9
i am not sure if this is what you wanted ...
What is the area of the shaded part of the figure?
Answer:
14cm²
Step-by-step explanation:
3x2=6,
3x2=6,
2x1=2,
6+6+2=14 cm^2
please help
Find the missing side of this right
triangle.
X
7
12
X
= [?]
Answer:
13.9 (if x is the Hypotenuse)
Step-by-step explanation:
which one is the Hypotenuse (the side opposite of the 90 degree angle) ?
because that determines the calculation.
if x is the Hypotenuse then Pythagoras looks like this
x² = 7² + 12² = 49 + 144 = 193
x = sqrt(193) = 13.9
if 12 is the Hypotenuse, then it looks like this
12² = 7² + x²
144 = 49 + x²
95 = x²
x = sqrt(95) = 9.75
Evaluate −a2+c2 when c=−4.
Answer:
[tex]a = 4, -4[/tex]
Step-by-step explanation:
Step 1: Plug in -4 for c
[tex]-a^{2} + c^{2}[/tex]
[tex]-a^{2} + (-4)^{2}[/tex]
[tex]-a^{2} + 16[/tex]
Step 2: Solve for a
[tex]-a^{2}+16-16=0-16[/tex]
[tex]-a^{2}/-1 = -16/-1[/tex]
[tex]a^{2} = 16[/tex]
[tex]\sqrt{a^{2}} = \sqrt{16}[/tex]
[tex]a = 4, -4[/tex]
Answer: [tex]a = 4, -4[/tex]
What type of object is pictured below?
O A. Point
O B. Ray
C. Segment
D. Line
Answer:
It is a ray because there are two points with a line passing through them which is extenging on one side but not on the other.