Long before music was recorded digitally, people listened to music played on phonographs.
An antiques dealer models the value of a vintage phonograph using the function V(t) =
0.04t? - 3t + 395, where V(t) is the value in dollars and t is the number of years since 1925.
The phonograph's value dropped as newer versions were introduced but then rose as it
became an antique.
In what year did the phonograph's value equal the value it had in the year 1925? What was
that value?
Round your answers to the nearest whole number.
The phonograph was worth $
value again in the year
in the year 1925. The phonograph had that same

Answer:

a : b : c = 9 : 15 : 20

Step-by-step explanation:

Here, b is common to both the ratios. In order to find the combined ratio of a, b and c, it is required to make the b ratio same in the given ratios.

Therefore,

[tex] \frac{a}{b} = \frac{3}{5} = \frac{3 \times 3}{5 \times 3} = \frac{9}{15} \\ \\ \frac{b}{c} = \frac{3}{4} = \frac{3 \times 5}{4 \times 5} = \frac{15}{20} \\ \\ \implies \: a : b : c = 9 : 15 : 20[/tex]

Answer:

Step-by-step explanation:

Tan(theta) = Sin(theta) / cos(theta)

1/4 = sin(theta) / sqrt(1 - sin^2(theta) )    Cross multiply

sqrt(1 - sin^2(theta)) = 4*sin^2(theta)      Square both sides.

1 - sin^2(theta) = 16 * sin^4 (theta)         Transfer the left side to the right side.

0 = 16 sin^4(theta) + sin^2(theta) - 1

Use the quadratic formula to find a value for sin^2(theta)

a = 16

b = 1

c = - 1

I'll leave solving the quadratic to you.

There are two answers

sin^2(theta)= .22069

The other root is - 0.28 which you cannot use.

Sin(theta) = +/- 0.4698

Cos(theta) is < 0 in quads 2 and 3

So sin(theta) is positive in quad 2

and sin(theta) is minus in quad 3

Answer:

linked the graph!

Step-by-step explanation:

Answer:

Using the slope-intercept form, the slope is −5

y=0,-1

Step-by-step explanation:

Answer:

Step-by-step explanation:

9514 1404 393

Answer:

  x = 60

Step-by-step explanation:

The angle x is half the sum of the intercepted arcs:

  x = (40 +80)/2

  x = 60

Answer:

x = 60°

Step-by-step explanation:

First find <E by applying the angles of intersecting chords theorem.

Based on the theorem, we would have the following equation:

m<E = ½(arc CA + arc BD)

Substitute

m<E = ½(170° + 70°)

m<E = ½(240)

m<E = 120°

Let's find x:

x = 180° - m<E (supplementary angles)

x = 180° - 120° (substitution)

x = 60°

Answer:

-4/-5

Step-by-step explanation:

you have to pick 2 numbers from the y row and the x row i picked -7 and 3 and -5 and 0 so first you would do 3-(-7) and that would be -4 and then do -5-0 and that would be -5 then you would put the y/x

Answer:

6.47

1.618 x 4 = 6.47

Step-by-step explanation:

Answer:

The length of golden rectangle is 6.5 cm.

Step-by-step explanation:

Definition of golden rectangle

The Golden Rectangle, also known as the perfect rectangle by some, is a rectangle with the Golden Ratio as its length to width ratio. Many people consider this to be one of the most visually appealing geometric shapes. Many works of art and architecture contain it.

Given the width of golden rectangle= 4 cm

and the golden ratio= 1.618

The golden ratio is the ratio of length and width [tex]l/b=1.618[/tex]

[tex]l=1.618*b\\=1.618*4\\=6.472 cm[/tex]

Now length of the rectangle is up to nearest tenth point=6.5 cm

Hence the length= 6.5 cm

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Answer:

2/15

Step-by-step explanation:

Answer:

30=6j

j=5

hope it helps .......

Answer:

a) test statistic = 2.12

b) p-value = 0.017

c) we reject the Null hypothesis

Step-by-step explanation:

Given data :

N = 200

girls (x) = 115 , Boys = 85

p = x / n = 115 / 200 = 0.575

significance level ( ∝ ) = 0.1

aim : test whether the proportion of girls births after the treatment is greater than 50% that occurs without any treatment .

A) Determine the test statistic

H0 : p = 0.5

Ha : p > 0.5

to determine the test statistic we will apply the z distribution at ( ∝ ) = 0.1

Z - test statistic = ( 0.575 - 0.5)  / [tex]\sqrt{0.5*0.5 / 200}[/tex]  = 2.12

b) determine the p-value

The P-value can be determined using the normal standard table

P-value = 1 - p(Z< 2.12 )  =  1 - 0.9830 = 0.017

c) Given that the p value ( 0.017 ) < significance level ( 0.1 )

we will reject the H0 because there is evidence showing that proportion of girls birth is > 50%

Answer:

Point

Step-by-step explanation:

Answer:

(-11/2; -4)

Step-by-step explanation:

The point that lies on the line is symmetry is the middle point of the segment

M(x) = (-8-3)/2 = -11/2

M(y) = -4

Answer:

(-11/2; -4)

Step-by-step explanation: The point that lies on the line is symmetry is the middle point of the segment

M(x) = (-8-3)/2 = -11/2

M(y) = -4

Answer:

7/9

Step-by-step explanation:

21 / 27 = 3 * 7 / 3 * 9

= 7/9

Answer:

0

Step-by-step explanation:

It is zero,   since -6+6 is bassicly 6-6 which is 0

Answer:

82

Step-by-step explanation:

Set the number of adult tickets sold as x. Then, the number of tickets for children would be 142-x

The total cost of all the tickets would be:

6.2(142 - x) + 9.9(x) = 1183.80

Simplify and solve

3.7x + 880.4 = 1183.8

3.7x = 303.4

x = 82

So, the answer is 82 tickets.

Answer:

132m^2

Step-by-step explanation:

Area=10x5+3x4x2/2+10x3+4x10

=50+12+30+40

=132

Answer: 132 meters squared

Step-by-step explanation:

We add all the sides of the shape:

Three quadrangular sides:

3 x 10 = 30

4 x 10 = 40

5 x 10 = 50

30 + 40 + 50 = 120

Two triangular sides:

3 x 4 / 2 = 6

3 x 4 / 2 = 6

6 + 6 = 12

We add all up:

120 + 12 = 132 meters squared

Answer:

A. Model B with the smaller standard deviation is preferable, because the smaller value implies that the mean is a more reliable representation of maintenance costs.

Step-by-step explanation:

The standard deviation is a measure of the variability of a dataset about a mean value. Larger values of standard deviation implies that the values varies Hugely about the mean whole smaller variability measure values mean that the data only varies a little about the mean. The implication of having a large variability value is that, low and high values in the data can be very different from the mean values, hence, lowering the reliability of Mean value. The lesser varibality gives the mean more reliability as a measure of centre

Answer:

Option C

Step-by-step explanation:

Given expression for the series is,

[tex]\sum_{j=2}^{10}(-2j+1)[/tex]

Here, j = Numbers of terms (from 2 to 10)

By substituting j = 2 to 10 we can find the terms of the series.

2, 3, 4, 5, 6, 7, 8, 9, 10

So the number of terms in the given series = 9

Option C will be the correct option.

Answer:

C) (0, -1) and ( [tex]\frac{1}{3}[/tex], 0)

Step-by-step explanation:

Move all terms to the left side and set equal to zero. Then set each factor equal to zero.

Exact Form:

z=0,7√8

Decimal Form:

z=0,1.34590019…

Hope this helps!

Have a great day!

- Hailey : )

Answer: 3 x 5²= 75

Step-by-step explanation:

How I got my answer was multiplying 3 x 5= 15 then 15 x 5=75 on my paper and that should be the right answer hope it help and the answer should be 75

Answer:

D. (1+1/n)n

Step-by-step explanation:

The value of the expression A, B, C, and D will be 1, ∞, ∞, and 1.

Algebra is the study of graphic formulas, while logic is the interpretation among those signs.

You can approximate e by substituting large values for n into the expression.

Let the infinity be the largest number.

A. (1 – 1/n)ⁿ

Substitute n = ∞, then the value of the expression will be

[tex]\Rightarrow \left (1 - \dfrac{1}{\infty} \right)^{\infty}\\\\\Rightarrow \left (1 - 0 \right)^{\infty}\\\\\Rightarrow 1[/tex]

B. (1 + n)ⁿ

Substitute n = ∞, then the value of the expression will be

[tex]\Rightarrow \left (1 + \infty \right)^{\infty}\\\\\Rightarrow \infty^{\infty} \\\\\Rightarrow \infty[/tex]

C. (1 – n)ⁿ

Substitute n = ∞, then the value of the expression will be

[tex]\Rightarrow \left (1 - \infty \right)^{\infty}\\\\\Rightarrow \infty^{\infty} \\\\\Rightarrow \infty[/tex]

D. (1 + 1/n)²

Substitute n = ∞, then the value of the expression will be

⇒ (1 + 1/∞)²

⇒ (1 + 0)²

⇒ 1²

⇒ 1

Then the value of the expression A, B, C, and D will be 1, ∞, ∞, and 1.

More about the Algebra link is given below.

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Answer:

45

Step-by-step explanation:

9 × 3 = 27

started with 72

72 - 27 = 45

Answer: Possibly -4

Step-by-step explanation:

But wait for others to check I’m not fully sure

Answer: 100

Step-by-step explanation:

200*10% or 200 * 0.10= 20

do the same for savings account 200*40%= 80

20 +80 = 100 subtract that from 200 she has 100 left.