A 60-watt light bulb advertises that it will last 1500 hours. The lifetimes of these light bulbs is approximately normally distributed with a mean of 1550 hours and a standard deviation of 57 hours. What proportion of these light bulbs will last less than the advertised time

Answer:

y = 1.8

Step-by-step explanation:

Question 39).

Let the operation which defines the relation between a and b is O.

Relation between a and b has been given as,

a O b = [tex]\frac{(a+b)}{(a-b)}[/tex]

Following the same operation, relation between 3 and y will be,

3 O y = [tex]\frac{3+y}{3-y}[/tex]

Since 3 O y = 4,

[tex]\frac{3+y}{3-y}=4[/tex]

3 + y = 12 - 4y

3 + y + 4y = 12 - 4y + 4y

3 + 5y = 12

3 + 5y - 3 = 12 - 3

5y = 9

[tex]\frac{5y}{5}=\frac{9}{5}[/tex]

y = 1.8

Therefore, y = 1.8 will be the answer.

Answer:

pleasse elaborate more

Step-by-step explanation:

Answer:

13°

Step-by-step explanation:

The trigonometric ratio formula can be used in calculating the angle of elevation (x°) of the sun, as the person makes a right angle with the ground.

The height of the person would be the opposite length = 6 ft, the shadow of the person would be the adjacent length = 26 ft

Therefore, according to the trigonometric ratio formula, we would calculate angle of elevation (x°) as follows:

[tex] tan x = \frac{opposite}{adjacent} [/tex]

[tex] tan x = \frac{6}{26} [/tex]

[tex] tan x = 0.2308 [/tex]

x = tan-¹(0.2308)

x = 12.996

x ≈ 13° (to the nearest whole degree)

The angle of elevation of the sun = 13°

Answer:

Step-by-step explanation:

The statement

3x less than two times the sum of 2X and one is written as

2( 2x + 1) - 3x

the sum of 2 and 5 is written as

2 + 5

Equate the two statements

We have

2( 2x + 1) - 3x = 2+5

Expand

4x + 2 - 3x = 7

Simplify

4x - 3x = 7 - 2

We have the final answer as

Hope this helps you

Answer:

its 14/C

Step-by-step explanation:

i got i right on edg U^U

Answer:

16

Step-by-step explanation:

i did edge test yea dont  be imma fake :***    

Answer:

[tex]m^3+m^2[/tex]

Step-by-step explanation:

=> [tex]2m^2-m^2(7-m)+6m^2[/tex]

Collecting like terms and expanding the brackets

=> [tex]2m^2+6m^2-7m^2+m^3[/tex]

=> [tex]8m^2-7m^2+m^3[/tex]

=> [tex]m^2+m^3[/tex]

=> [tex]m^3+m^2[/tex]

Answer:

Aquarium dimensions:

x = 3,106 m

h = 6,22 m

C(min) = 1277,62 $

Step-by-step explanation: (INCOMPLETE QUESTION)

We have to assume:

The shape of the aquarium  (square base)

Let´s call "x" the side of the base, then h ( the heigh)

V(a) = x²*h          h = V(a)/x²      

Cost of Aquarium   C(a) = cost of the base (in stones) + 4* cost of one side (in glass)

C(a) = Area of the base *120 + 4*Area of one side*30

Area of the base is x²

Area of one side  is   x*h   or  x*V(a)/x²  

Area of one side is V(a)/x

C(x) = 120*x² + 4*30*60/x

C(x) = 120*x² +  7200/x

Taking derivatives on both sides of the equation we get

C´(x) = 2*120*x  - 7200/x²

C´(x) = 0 means    240 *x  - 7200/x² = 0

240*x³ - 7200 = 0

x³ = 7200/240

x = 3,106 m   and  h = 60 /x²     h =   6,22 m

and C (min) = 120*(3,106)³ - 7200 / 3,106

C(min) =  3595,72 - 2318,1

C(min) = 1277,62

Answer:

x = -1.964636

Step-by-step explanation:

Given equation;

eˣ = 4 - x²

This can be re-written as;

eˣ - 4 + x² = 0

Let

f(x) = eˣ - 4 + x²    -----------(i)

To use Newton's method, we need to get the first derivative of the above equation as follows;

f¹(x) = eˣ - 0 + 2x

f¹(x) = eˣ + 2x         -----------(ii)

The graph of f(x) has been attached to this response.

As shown in the graph, the curve intersects the x-axis twice - around x = -2 and x = 1. These are the approximate roots of the equation.

Since the question requires that we use the negative root, then we start using the Newton's law with a guess of x₀ = -2 at n=0

From Newton's method,

[tex]x_{n+1} = x_n + \frac{f(x_{n})}{f^1(x_{n})}[/tex]

=> When n=0, the equation becomes;

[tex]x_{1} = x_0 - \frac{f(x_{0})}{f^1(x_{0})}[/tex]

[tex]x_{1} = -2 - \frac{f(-2)}{f^1(-2)}[/tex]

Where f(-2) and f¹(-2) are found by plugging x = -2 into equations (i) and (ii) as follows;

f(-2) = e⁻² - 4 + (-2)²

f(-2) = e⁻² = 0.13533528323

And;

f¹(2) = e⁻² + 2(-2)

f¹(2) = e⁻² - 4 = -3.8646647167

Therefore

[tex]x_{1} = -2 - \frac{0.13533528323}{-3.8646647167}[/tex]

[tex]x_{1} = -2 - \frac{0.13533528323}{-3.8646647167}[/tex]

[tex]x_{1} = -2 - -0.03501863503[/tex]

[tex]x_{1} = -2 + 0.03501863503[/tex]

[tex]x_{1} = -1.9649813649[/tex]

[tex]x_{1} = -1.96498136[/tex]         [to 8 decimal places]

=> When n=1, the equation becomes;

[tex]x_{2} = x_1 - \frac{f(x_{1})}{f^1(x_{1})}[/tex]

[tex]x_{2} = -1.96498136 - \frac{f(-1.9649813)}{f^1(-1.9649813)}[/tex]

Following the same procedure as above we have

[tex]x_{2} = -1.96463563[/tex]

=> When n=2, the equation becomes;

[tex]x_{3} = x_2 - \frac{f(x_{2})}{f^1(x_{2})}[/tex]

[tex]x_{3} = -1.96463563- \frac{f( -1.96463563)}{f^1( -1.96463563)}[/tex]

Following the same procedure as above we have

[tex]x_{3} = -1.96463560[/tex]

From the values of [tex]x_2[/tex] and [tex]x_3[/tex], it can be seen that there is no change in the first 6 decimal places, therefore, it is safe to say that the value of the negative root of the equation is approximately  -1.964636 to 6 decimal places.

Newton's method of approximation is one of the several ways of estimating values.

The approximated value of [tex]\mathbf{e^x = 4 - x^2}[/tex] to 6 decimal places is [tex]\mathbf{ -1.964636}[/tex]

The equation is given as:

[tex]\mathbf{e^x = 4 - x^2}[/tex]

Equate to 0

[tex]\mathbf{4 - x^2 = 0}[/tex]

So, we have:

[tex]\mathbf{x^2 = 4}[/tex]

Take square roots of both sides

[tex]\mathbf{ x= \pm 2}[/tex]

So, the negative root is:

[tex]\mathbf{x = -2}[/tex]

[tex]\mathbf{e^x = 4 - x^2}[/tex] becomes [tex]\mathbf{f(x) = e^x - 4 + x^2 }[/tex]

Differentiate

[tex]\mathbf{f'(x) = e^x +2x }[/tex]

Using Newton's method of approximation, we have:

[tex]\mathbf{x_{n+1} = x_n - \frac{f(x_n)}{f'(x_n)}}[/tex]

When x = -2, we have:

[tex]\mathbf{f'(-2) = e^{(-2)} +2(-2) = -3.86466471676}[/tex]

[tex]\mathbf{f(-2) = e^{-2} - 4 + (-2)^2 = 0.13533528323}[/tex]

So, we have:

[tex]\mathbf{x_{1} = -2 - \frac{0.13533528323}{-3.86466471676}}[/tex]

[tex]\mathbf{x_{1} = -2 + \frac{0.13533528323}{3.86466471676}}[/tex]

[tex]\mathbf{x_{1} = -1.96498136}[/tex]

Repeat the above process for repeated x values.

We have:

[tex]\mathbf{x_{2} = -1.96463563}[/tex]

[tex]\mathbf{x_{3} = -1.96463560}[/tex]

Up till the 6th decimal places,

[tex]\mathbf{x_2 = x_3}[/tex]

Hence, the approximated value of [tex]\mathbf{e^x = 4 - x^2}[/tex] to 6 decimal places is [tex]\mathbf{ -1.964636}[/tex]

Read more about Newton approximation at:

https://brainly.com/question/14279052

Answer:

The expression that fits into the box is x¹⁵⁸

Step-by-step explanation:

Let the empty box be y

(x¹²)⁵ × (x⁻²)⁹ × y = (x⁴⁰)⁵

Here, we will apply the laws of indices.

The laws of indices gives the answer for the expressions

1) xᵏ × xˢ = xᵏ⁺ˢ

2) xᵏ ÷ xˢ = xᵏ⁻ˢ

3) (xᵏ)ˢ = xᵏ•ˢ

So,

(x¹²)⁵ = x⁶⁰

(x⁻²)⁹ = x⁻¹⁸

(x⁴⁰)⁵ = x²⁰⁰

(x¹²)⁵ × (x⁻²)⁹ × y = (x⁴⁰)⁵

Becomes

x⁶⁰ × x⁻¹⁸ × y = x²⁰⁰

x⁶⁰⁻¹⁸ × y = x²⁰⁰

x⁴² × y = x²⁰⁰

y = x²⁰⁰ ÷ x⁴²

y = x²⁰⁰⁻⁴² = x¹⁵⁸

Hope this Helps!!!

Answer:  B) 10 three-point questions and 14 five-point questions

Step-by-step explanation:

x represents three-point questions

y represents five-point questions

3x + 5y = 100  →  1(3x + 5y = 100)  =  3x + 5y = 100

 x  +  y  = 24   → -3(x  +  y  = 24)   = -3x  -3y  = -72

                                                                  2y = 28

                                                                    y = 14  (five-point questions)

x +  y = 24

x + 14 = 24

     x = 10  (three-point questions)

Answer:

The correct answer is option a.

a. 5( √3+ 1 )

Step-by-step explanation:

Given that the angle changes from 45° to 60° in 10 minutes.

This situation can be represented as right angled triangles [tex]\triangle[/tex]ABC (in the starting when angle is 45°)and [tex]\triangle[/tex]ABD (after 10 minutes when the angle is 60°).

AB is the tower (A be its top and B be its base).

Now, we need to find the time to be taken to cover the distance D to B.

First of all, let us consider [tex]\triangle[/tex]ABC.

Using tangent property:

[tex]tan\theta =\dfrac{Perpendicular}{Base}\\\Rightarrow tan 45=\dfrac{AB}{BC}\\\Rightarrow 1=\dfrac{h}{BC}\\\Rightarrow h = BC[/tex]

Using tangent property in [tex]\triangle[/tex]ABD:

[tex]\Rightarrow tan 60=\dfrac{AB}{BD}\\\Rightarrow \sqrt3=\dfrac{h}{BD}\\\Rightarrow BD = \dfrac{h}{ \sqrt3}\ units[/tex]

Now distance traveled in 10 minutes, CD  = BC - BD

[tex]\Rightarrow h - \dfrac{h}{\sqrt3}\\\Rightarrow \dfrac{(\sqrt3-1)h}{\sqrt3}[/tex]

[tex]Speed =\dfrac{Distance }{Time}[/tex]

[tex]\Rightarrow \dfrac{(\sqrt3-1)h}{10\sqrt3}[/tex]

Now, we can say that more distance to be traveled to reach the base of tower is BD i.e. '[tex]\bold{\dfrac{h}{\sqrt3}}[/tex]'

So, more time required = Distance left divided by Speed

[tex]\Rightarrow \dfrac{\dfrac{h}{\sqrt3}}{\dfrac{(\sqrt3-1)h}{10\sqrt3}}\\\Rightarrow \dfrac{h\times 10\sqrt3}{\sqrt3(\sqrt3-1)h}\\\Rightarrow \dfrac{10 (\sqrt3+1)}{(\sqrt3-1)(\sqrt3+1)} (\text{Rationalizing the denominator})\\\Rightarrow \dfrac{10 (\sqrt3+1)}{3-1}\\\Rightarrow \dfrac{10 (\sqrt3+1)}{2}\\\Rightarrow 5(\sqrt3+1)}[/tex]

So, The correct answer is option a.

a. 5( √3+ 1 )

Answer:

-21/5 = -4.2

Step-by-step explanation:

-21.87 / 4.79 = -4.5657.....

So, the quotients is -4

Now, Let's see who's quotient is equal to think one:

-21/4 = -5.25

-21/5 = -4.2

-40/4 = -5

-20/5 = 4

Answer:

-21/5 = -4.2

Step-by-step explanation:

Answer:

The answer is

Step-by-step explanation:

Equation of a line is y = mx + c

where

m is the slope

c is the y intercept

From the question

Slope / m = 5

Equation of the line passing through point (2 , 10) is

y - 10 = 5(x - 2)

y - 10 = 5x - 10

y = 5x - 10 + 10

Hope this helps you

Answer:

critical point of the given function f(x,y) = x²+y²+2xy is from line y = -x is the critical point of the function f(x0,y0) = 0

and it local minimum.

Step-by-step explanation:

Let the given function be;

f(x,y) = x²+y²+2xy

From above function, we can locate relative minima, maxima and the saddle point

f(x,y) = x²+y²+2xy = (x+y)²

df/dx = 2x+2y = 0 ---- (1)

df/dy =2y+2x = 0 ---- (2)

From eqn 1 and 2 above,

The arbitrary point (x0,y0) from line y = -x is the critical point of the function f(x0,y0) = 0

Then, from f(x,y) >= 0 for arbitrary (x,y) € R^n, the arbitrary point from the line x = -y is local minima of the function f.

Answer:

b, c, e

Step-by-step explanation:

the reasons have to include an angle from both of the parallel lines. by using process of elimination it is b, c, e. I also got it right

Answer:

B. a=d

C. c=d

E. b + d=180°

Step-by-step explanation:

Got Correct On MyPath.

Answer:

Probability ball is an even numbered ball or a 4 [P(A or B)] = 9 / 19

Step-by-step explanation:

Given:

Number of balls = 1 to 19

Find:

Probability ball is an even numbered ball or a 4

Computation:

Total even number = 2, 4, 6, 8, 10, 12, 14, 16, 18

Probability to get even number P(A) = 9 / 19

Probability to get 4 number P(B) = 1 / 19

P(A and B) = 1 / 19 (4 common)

Probability ball is an even numbered ball or a 4 [P(A or B)]

P(A or B) = P(A) + P(B) -P(A and B)

P(A or B) = [9 / 19] + [1 / 19] - [1 / 19]

Probability ball is an even numbered ball or a 4 [P(A or B)] = 9 / 19

Answer:

-3x^2 -5x +2

Step-by-step explanation:

-2x(x+3)-(x+1)(x-2)=

Distribute

-2x^2 -6x  -(x+1)(x-2)

Foil

-2x^2 -6x  -(x^2 -2x +x -2)

Combine like terms

-2x^2 -6x  -(x^2 -x  -2)

Distribute the minus sign

-2x^2 -6x  -x^2  +x +2

Combine like terms

-2x^2  -x^2  -6x +x +2

-3x^2 -5x +2

Answer:

[tex]\huge\boxed{-2x(x+3)-(x+1)(x-2)=-3x^2-5x+2}[/tex]

Step-by-step explanation:

[tex]-2x(x+3)-(x+1)(x-2)[/tex]

Use the distributive property: a(b + c) = ab + ac

and FOIL: (a + b)(c + d) = ac + ad + bc + bd

[tex]=(-2x)(x)+(-2x)(3)-\bigg[(x)(x)+(x)(-2)+(1)(x)+(1)(-2)\bigg]\\\\=-2x^2-6x-\bigg(x^2-2x+x-2\bigg)=-2x^2-6x-x^2-(-2x)-x-(-2)\\\\=-2x^2-6x-x^2+2x-x+2[/tex]

Combine like terms:

[tex]=(-2x^2-x^2)+(-6x+2x-x)+2=-3x^2+(-5x)+2\\\\=-3x^2-5x+2[/tex]

Answer:

4 : 5

Step-by-step explanation:

you can divide 120 and 150 by 30 and 8 and 10 by 2.

120/30 = 4

150/30 = 5

8/2 = 4

10/2=5

Answer: 4:5

Step-by-step explanation:

Answer:

52

Step-by-step explanation:

a(n)=-5+(n-1)3

a(20)=-5+(20-1)3

a(20)=52

The 20th term of the arithmetic sequence is 52.

An arithmetic sequence is a list of numbers with a definite pattern. If you take any number in the sequence then subtract it by the previous one, and the result is always the same or constant then it is an arithmetic sequence.

For example,

In an arithmetic sequence, the difference between consecutive terms is always the same. For example, the sequence 3, 5, 7, 9 ... is arithmetic because the difference between consecutive terms is always two.

The nth term of an arithmetic sequence is given by an = a + (n – 1)d.

Given:

a(n)=-5+(n-1)3

First term,

a(1)= -5 + 0

a(1)= -5

second, a(2)= -5 + 1*3

a(2)= -2

Third, a(3)= -5+6

a(3)= 1

d= 3

So, the 20th term

a(20)= -5+ (20-1)3

a(20)= -5 + 57

a(20)= 52

Hence, the 20th term is 52.

Learn more about Arithmetic Sequence here:

https://brainly.com/question/10396151

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Answer: Use calculations for population standard deviation.

Step-by-step explanation:

The population standard deviation is defined as

A sample standard deviation is defined as

Since, data set represents the heights of all students in the middle school with 600 students which is population here.

So, we do calculations to find population standard deviation.

Answer:

pay the 11 AM ticket

Step-by-step explanation:

Note that the flight last for 12 hours, and assuming the freelance developer can still work (have access to the internet) on the airplane throughout the flight, he stand to earn $960 ($80*12), which will still cover the cost of the flight with a profit of $60 ($960-900).

However, if he decides to pay the $11 flight ticket and there is no Internet on boards; there by losing a day of work, he stand to have lost working time which would earn with $900.

Therefore, the best choice is to pay the 11 AM ticket.

Answer:

-20

Step-by-step explanation:

Follow the PEDMAS order (from top to bottom):

Parentheses

Exponents

Division and Multiplication

Addition and Subtraction

(-5 × 9 - 1) ÷ 2 + (5)2 - 7

(-45 - 1) ÷ 2 + 10 - 7

-46 ÷ 2 + 10 - 7

-23 + 10 - 7

-13 - 7

-20

Answer:

-20

Step-by-step explanation:

=> [tex](-5 * 9-1)/2+(5)2-7[/tex]

Expanding parenthesis

=> [tex](-45-1)/2+10-7[/tex]

=> [tex]-46/2 + 3[/tex]

=> -23 + 3

=> -20

Answer:

The possible arrangement= 18 ways

Step-by-step explanation:

Six identical coin are tossed.

Coin has only a tail and a head.

In how many possible ways can the arrangement be 3 head and 3 tail.

The possible arrangement= (3! * 3!)/2

The reason for dividing by two because coin has two face.

The possible arrangement= (3! * 3!)/2

The possible arrangement=( 6*6)/2

The possible arrangement= 36/2

The possible arrangement= 18 ways

Answer:

y = -(1/2)x+1

Step-by-step explanation:

-2Y - X = -2

Add x to both sides:

-2Y = X - 2

Divide both sides by -2:

Y = -(1/2)x+1

You could also use the shortcuts:

For Ay+Bx=C, the slope is -B/A and the y-intercept is C/A.

Slope = -B/A = -(-1)/(-2) = 1/-2 = -(1/2)

Y-intercept = C/A = (-2)/(-2) = 1

y = mx + b ---> y = -(1/2)x + 1

Answer:

y = -1/2x +1

Step-by-step explanation:

The slope intercept form of a line is

y = mx+b where m is the slope and b is the y intercept

-2y -x = -2

Solve for y

Add x to each side

-2y = x-2

Divide by -2

-2y/2- = x/-2 -2/-2

y = -1/2x +1

Answer:

0.38

Step-by-step explanation:

The area under the probability density curve is equal to 1.

The width of the rectangle is 2, so the height of the rectangle must be ½.

The probability that X is between 0.68 and 1.44 is therefore:

P = ½ (1.44 − 0.68)

P = 0.38

Using the uniform distribution, it is found that there is a 0.38 = 38% probability that X is between 0.68 and 1.44.

-----------------------

Uniform probability distribution:

[tex]P(c \leq X \leq d) = \frac{d - c}{b - a}[/tex]

In this problem:

The probability that X is between 0.68 and 1.44 is:

[tex]P(0.68 \leq X \leq 1.44) = \frac{1.44 - 0.68}{2 - 0} = 0.38[/tex]

0.38 = 38% probability that X is between 0.68 and 1.44.

A similar problem is given at https://brainly.com/question/13547683

Answer:

1112

Step-by-step explanation:

6458 + 2994  = 9452

7013  - 6945  = 68

9452/68 = 139

139 * 8 = 1112

​

Answer:

A. 1 4/6 cups of blueberries

Step-by-step explanation:

1 -- 2/3                      

Proportion, Batches to Blueberries

1*(2 1/2) -- (2/3)( 2 1/2)              

Because we are now multiplying the 1 batch to 2 1/2 batches. So to keep the proportion balanced/equal we are using the same operation on the right side of the proportion

2 1/2 -- (2/3)( 5/2 )      

2 1/2 -- 5/3

2 1/2 -- 1 2/3

Simplify

On the right side shows the blueberries for 2 1/2 batches. 1 2/3 = 1 4/6    

Hope that helps! Tell me if you need more info

Answer: $34.18

Step-by-step explanation:

Let the cost of the Jacket = $x and

The cost of the sweater. = $y

Now total price. = $71.55.

So, $x + $y. = $71.55 -- 1

From the second statements, the price of the sweater was $3.19 less than the price of the jacket. Transforming that into equation

y = ( x - $3.19 )

Now substitute for y in the equation (1) above.

x + ( x - 3.19 ) = 71.55

Now solve the equation

x + x - 3.19 = 71.55

2x - 3.19. = 71.55

2x = 71.55 + 3.19

2x. = 74.74

x = 74.74/2

= $37.37. cost of the jacket

Now to determine the cost of the sweater,

$71.55 - $37.37 = $34.18

The cost of the sweater = $34.18.

Answer:

$1387.4

Step-by-step explanation:

Total cost for the computer will be sum of down payments and monthly installments.

____________________________________

Given

down payment = $200

monthly installment value = $98.85

no. of installments = 12

total value of monthly installments = 12*98.95 = $1187.4

Total cost of computer system = $200+  $1187.4 = $1387.4

Answer:

answer D

Step-by-step explanation:

Lets have a look to the graph and to the  each of given functions.

As we can see in graph it intersects X in points (-3;0) and (-6;0) that means the function has the roots x1=-3 and x2=-6

Function A  has the roots x1=+3 and x2=+6 => doesn' t fit

Function B has only 1 root x=2 , so can be factorized y=(x-2)^2 => doesn' t fit

Function C has 2 roots  x1=4  and x2=-5 => doesn' t fit

Function D can be factotized as y=(x+6)*(x+3) so has 2 roots x1=-6 x2=-3 => exactly what we need!!!

We can also notice that the coefficient near x²  is equal to 1  and is positive.

That means the legs of the graph directed up,- this is exactly like in our graph. It gives us extra argument why we choose D.