round 12.5478 to the nearest hundredths

Answers

Answer 1

Answer:

12.04

Step-by-step explanation:

Find the number in the hundredth place  4  and look one place to the right for the rounding digit  1 . Round up if this number is greater than or equal to  5  and round down if it is less than  5 .


Related Questions

Suppose that a customer is purchasing a car. He conducts an experiment in which he puts 10 gallons of gas in the car and drives it until it runs out of gas. He conducts this experiment 15 times on each car and records the number of miles driven.

Car 1 Car 2
214 220
245 221
239 244
224 225
220 258
295 259

Describe each data set, that is determine the shape, center, and spread

i. Sample mean for Car 1
ii. Sample mean for Car 2

Answers

Answer:

Kindly check explanation

Step-by-step explanation:

Given the data :

Car 1 Car 2

214 220

245 221

239 244

224 225

220 258

295 259

Ordered data:

Car 1 : 214, 220, 224, 239, 245, 295

Sample mean = ΣX/ n ; n = sample size = 6

Sample mean = 1437 / 6 = 239.5

Median = 1/2(n+1)th term = 1/2(7) = 3.5th term

Median = (3rd + 4th) /2 = (224 + 239) /2 = 231.5

Sample standard deviation; √(Σ(x - xbar)²/n-1 ) = 29.60 (using calculator)

Car 2 : 220, 221, 225, 244, 258, 259

Sample mean = ΣX/ n ; n = sample size = 6

Sample mean = 1427 / 6 = 237.833

Median = 1/2(n+1)th term = 1/2(7) = 3.5th term

Median = (3rd + 4th) /2 = (225 + 244) /2 = 234.5

Sample standard deviation; √(Σ(x - xbar)²/n-1 ) = 18.21 (using calculator)

so sánh 198*202 và 200^2

Answers

Step-by-step explanation:

198×202=39,996

200×200=40,000

hence,

39,9996 < 40,000

hope it helps

represent (-12)+(-8)+14 on a number line​

Answers

Answer:

-6

Step-by-step explanation:

(-12)+(-8)= -20

-20+14= -6

MY NOTES Verify that the function satisfies the three hypotheses of Rolle's Theorem on the given interval. Then find all numbers c that satisfy the conclusion of Rolle's Theorem. (Enter your answers as a comma-separated list.) f(x) = 2x2 − 4x + 3, [−1, 3

Answers

Answer:

b)  [tex]c=1[/tex]

Step-by-step explanation:

From the question, we are told that:

Function

[tex]F(x)=2x^2-4x+9[/tex]

Given

Rolle's theorem states that if a function f is continuous on the closed interval [a, b] and differentiable on the open interval (a, b) such that f(a) = f(b), then f′(x) = 0 for some x with a ≤ x ≤ b.

Generally, the Function above is a polynomial that can be Differentiated and it is continuous

Where

-F(x) is continuous at (-1,3)

-F(x) Can be differentiated at (-1.3)

-And F(-1)=F(3)

Therefore

F(x) has Satisfied all the Requirements for Rolle's Theorem

Differentiating F(x) we have

[tex]F'(x)=4x-4[/tex]

Equating F(c) we have

[tex]F'(c)=0[/tex]

[tex]4(c)-4=0[/tex]

Therefore

[tex]c=1[/tex]

A spinner contains the numbers 1 through 50. What is the probability that the spinner will land on a number that is not a multiple of 8?

Answers

Answer:

22/25

Step-by-step explanation:

Multiples of 8 are 8,16,24,32,40,48

That means there are 6 multiples of 8

50 -6 = 44

There are 44 non multiples of 8

P( non multiples of 8) = non multiples of 8 / total

                                   = 44/50

                                  =22/25

What is the approximate length of arc s on the circle below? Use 3.14 for Pi. Round your answer to the nearest tenth.

-5.8 ft
-6.3 ft
-27.5 ft
-69.1 ft

Answers

9514 1404 393

Answer:

  69.1 ft

Step-by-step explanation:

The diameter of the circle is 24 ft. The length of the arc is more than twice the diameter, so cannot be less than about 50 ft. The only reasonable choice is ...

  69.1 ft

__

The circumference of the circle is ...

  C = 2πr = 2(3.14)(12 ft) = 75.36 ft

The arc length of interest is 330° of the 360° circle, so is 330/360 = 11/12 times the circumference.

  s = (11/12)(75.36 ft) = 69.08 ft ≈ 69.1 ft

Answer:D

Step-by-step explanation:

A ladder 10m long is set against a vertical wall, Calculate the height of the wall where the ladder reached a foot of the ladder is 6m away from the wall.

Answers

Answer:

8m

Step-by-step explanation:

A car rental firm has 440 cars. Sixty-three of these cars have defective turn signals and 39 have defective tires. (Enter your probabilities as fractions.) (a) What is the probability that one of these cars selected at random does not have defective turn signals

Answers

Answer:

The probability is 0.857

Step-by-step explanation:

We know that:

There is a total of 440 cars

There are 63 cars with defective turn signals

There are 39 with defective tires.

Now we want to find the probability that a randomly selected car does not have defective turn signals.

If all the cars have the same probability of being selected, this probability will be equal to the quotient between the number of cars that do not have defective turn signals and the total number of cars.

We know that the total number of cars is 440

And 63 of these have defective turn signals, then the rest don't.

440 - 63 = 377 cars do not have defective turn signals.

Then the probability is:

P = 377/440 = 0.857

An exponential function f(x) = ab^xpasses through the points (0, 2) and (3, 54). What are the values of a and
b?
a=
b =

Answers

Answers:

a = 2

b = 3

=======================================================

Explanation:

Plug in x = 0 and y = 2 to find that

y = a*b^x

2 = a*b^0

2 = a*1

2 = a

a = 2

Then plug in x = 3 and y = 54 to determine the value of b

y = a*b^x

y = 2*b^x

54 = 2*b^3

2b^3 = 54

b^3 = 54/2

b^3 = 27

b = (27)^(1/3)

b = 3

So we have y = a*b^x update to y = 2*3^x

The principal amount of money for this loan is $9,500.00. If you deposit this into an account paying 4.2% annual interest compounded monthly. How much money will be in the account after 5 years? (also called Future value).

Answers

9514 1404 393

Answer:

  $11,715.65

Step-by-step explanation:

The applicable formula is ...

  FV = P(1 +r/n)^(nt)

where principal P earns interest at rate r compounded n times per year for t years.

  FV = $9500(1 +0.042/12)^(12·5) = $9500(1.0035^60) ≈ $11,715.65

The account will hold $11,715.65 after 5 years.

The price of a item has reduced by 85% the original price was $60

Answers

Answer:

The price now would be 9 dollars

Step-by-step explanation:

60 x 85%  is 51 and you subtract that from 60

Find the length represented by x for each pair of similar triangles.
18cm, 9cm, and x
30cm, 15cm, and 25cm

Answers

Answer:

15 cm

Step-by-step explanation:

Since the traingles are similar, we can find the ratio between the side lengths, and it will be the same for each side.

We can use the side length 9 and 15 to find this ratio. 15/9=5/3. So, the ratio of a side length of the larger triangle to the smaller one is 5/3, so our equation becomes 5/3 = 25/x. Use any method you like to find that x=15.

Hope this helped,

~cloud

Which graph represents the function f(x) = x-2?

Answers

Answer:

click in photo

nejdjjd

nxndjdbbdjf

lấy x=0 ta có y= -2 => A(0;-2)

lấy y=0 ta có x=2 => B(2;0)

nối 2 điểm A và B ta có đồ thị:

The state education commission wants to estimate the fraction of tenth grade students that have reading skills at or below the eighth grade level.
Step 1 of 2: Suppose a sample of 2845 tenth graders is drawn. Of the students sampled, 2276 read above the eighth grade level. Using the data, estimate the proportion of tenth graders reading at or below the eighth grade level. Enter your answer as a fraction or a decimal number rounded to three decimal places.
Step 2 of 2: Suppose a sample of 2845 tenth graders is drawn. Of the students sampled, 2276 read above the eighth grade level. Using the data, construct the 99% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level. Round your answers to three decimal places.

Answers

Answer:

Step 1: The estimate the proportion of tenth graders reading at or below the eighth grade level is 0.2.

Step 2: The 99% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level is (0.181, 0.219).

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.

[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

In which

z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].

Suppose a sample of 2845 tenth graders is drawn. Of the students sampled, 2276 read above the eighth grade level.

So 2845 - 2276 = 569 read below, and the estimate of the proportion of tenth graders reading at or below the eighth grade level is:

[tex]\pi = \frac{569}{2845} = 0.2[/tex], and the answer to step 1 is 0.2.

The sample size is [tex]n = 2845[/tex]

99% confidence level

So [tex]\alpha = 0.01[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.01}{2} = 0.995[/tex], so [tex]Z = 2.575[/tex].  

The lower limit of this interval is:

[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.2 - 2.575\sqrt{\frac{0.2*0.8}{2845}} = 0.181[/tex]

The upper limit of this interval is:

[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.2 + 2.575\sqrt{\frac{0.2*0.8}{2845}} = 0.219[/tex]

The 99% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level is (0.181, 0.219).

25(0.3x-4)-5(1.5x-6)+100(13/4) simplify the following expression and evaluate for x=0.345

Answers

Answer:

255

Step-by-step explanation:

Given :

Simplify the expression :

25(0.3x-4)-5(1.5x-6)+100(13/4)

Open each Bracket:

7.5x - 100 - 7.5x + 30 + 325

7.5x - 7.5x - 100 + 30 + 325

= 255

The simplified equation = 255

Cho hình hộp chữ nhật ABCD A B C D

Answers

Answer:

A B C D

A×B×C×D

3×3×3×6

162

A bucket contains 4 red balls that are numbered 1, 2, 3, 4. It also contains 6 black balls that are numbered 5, 6, 7, 8, 9, 10. Two balls are drawn from the bucket, one at a time, without replacement. Use this information to answer the following probability questions. Express answers as fractions, or round decimal answers to 4 decimal places. a. What is the probability that the first ball is even and the second ball is odd

Answers

The probability is 1/9

We want to find the probability that the first drawn ball is even, and the second is odd.

The probability of randomly drawing an even ball will be equal to the quotient between the number of balls with even numbers and the total number of balls in the bucket.

We have a total of 10 balls (4 red ones and 6 black ones)

and 5 of these have even numbers (2, 4, 6, 8, 10)

Then the probability of drawing a ball with an even number first is:

p = 5/10 = 1/5

now we want to get a ball with an odd number.

notice that we already got a ball with an even number and we did not replace it, so now there are 9 balls left in the bucket, 5 odd ones, and 4 even ones.

The probability of getting an odd ball is computed in the same way thana above, as the quotient between the number of balls with odd numbers (5) and the total number of balls in the bucket (9)

q = 5/9

The joint probability (the probability that these two events happen together) is equal to the product of the individual probabilities, so we will get:

P = p*q = (5/9)*(1/5) = 1/9

The probability is 1/9

If you want to learn more about this topic, you can read:

https://brainly.com/question/24280250

What is the sum (6x^3 – 5x^2 + 3x – 5) + (8x^4 + 3x^3 + 5x^2 + x + 4)?

A.9x^6 + 8x^4 + 4x^2 – 1
B.8x^4 + 9x^3 + 4x – 1
C.8x^4 + 3x^3 – 10x^2 + 4x – 1
D.8x^4 – 3x^3 + 10x^2 – 2x + 9

Answers

Answer:

8x^4+9x^3+4x-1

Step-by-step explanation:

(6x^3 – 5x^2 + 3x – 5) + (8x^4 + 3x^3 + 5x^2 + x + 4)

Group like terms

8x^4+6x^3+3x^3-5x^2+5x^2+3x+x-5+4

8x^4+9x^3+4x-1

Answer:

[tex]\left(6x^3-5x^2+3x-5\right)+\left(8x^4+3x^3+5x^2+x+4\right)[/tex]

Combine like terms

[tex]=8x^4+6x^3+3x^3-5x^2+5x^2+3x+x-5+4[/tex]

Add: -5x²+5x²=0

[tex]=8x^4+6x^3+3x^3+3x+x-5+4[/tex]

Now add 6x³+3x³=9x³

[tex]=8x^4+9x^3+3x+x-5+4[/tex]

Add like terms 3x +x=4x

[tex]=8x^4+9x^3+4x-5+4[/tex]

Now add -5+4=-1

[tex]=8x^4+9x^3+4x-1[/tex]

OAmalOHopeO

Which of the following rational functions is graphed below?
o
A. F(x) = 1/2x
B. AX) = 1/x-2
C. F(x) = 1/x+2

Answers

Answer:

Option B.

Step-by-step explanation:

We can see that we have an asymptote at x = 2

Remember that in a rational function, the asymptote is at the x-value such that the denominator is equal to zero.

So, the denominator is something like:

(x + a)

we have that the denominator is zero when x = 2

Then:

(2 + a) = 0

solving that for a, we get:

a = -2

Then the denominator of the rational function is:

(x - 2)

For the given options, the only one with this denominator is option B, then the correct option is B.

Answer:

B. f(x) = 1/x-2

Step-by-step explanation:

Math is ez bro.

find the sum of (-260)+(-30)​

Answers

Answer:

-290

Step-by-step explanation:

(-260) +(-30)

=-260-30

=-290

Answer:

the answer is -290

Step-by-step explanation:

it is telling us to add so we can see that both the numbers have the same sign which is negative

when the signs are all the same, we can add and we got -290

The graphs of exponential functions f and g are shown on the coordinate plane below.

Answers

9514 1404 393

Answer:

  k = 3

Step-by-step explanation:

It is convenient to look at the line y=1 to see that f(0) = 1 and g(3) = 1. Then for x=3, g(3) = f(3 -k) = f(0) = 1

  k = 3

__

k is the amount by which the function has been shifted to the right. By comparing grid-intersection points on f(x) and g(x), we see that g(x) is 3 units to the right of f(x), so k = 3.

Which of the following statements are true?

Answers

Answer:

last one

Step-by-step explanation:

they both whole

Please show your work this question what made you come to the conclusion. Thank you

Answers

Answer:

B the range, the x- and y-intercept

Step-by-step explanation:

the domain stays the same : all values of x are possible out of the interval (-infinity, +infinity).

but the range changes, as for the original function y could only have positive values - even for negative x.

the new function has a first term (with b) that can get very small for negative x, and then a subtraction of 2 makes the result negative.

the y-intercept (x=0) of the original function is simply y=1, as b⁰=1.

the y-intercept of the new function is definitely different, because the first term 3×(b¹) is larger than 3, because b is larger than 1. and a subtraction of 2 leads to a result larger than 1, which is different to 1.

the original function has no x-intercept (y=0), as this would happen only for x = -infinity. and that is not a valid value.

the new function has an x-intercept, because the y-values (range) go from negative to positive numbers. any continuous function like this must therefore have an x-intercept (again, y = the function result = 0)

[tex] 3 {b}^{x + 1} = 2[/tex]

[tex] {b}^{x + 1} = 2 \div 3[/tex]

[tex] log_{b}(2 \div 3) = x + 1[/tex]

[tex]x = log_{b}(2 \div 3) - 1[/tex]


Family Video stocks 1003 drama movies, 518 science fiction movies and
253 children's movies. How many more drama titles than children's
titles does Family Video have in stock?

Answers

Answer:

There are 750 more drama movies that children's movies.

Step-by-step explanation:

There are 1003 drama movies, and 253 children's movies.

1003 - 253 = 750

Thank you guys fir the help

Answers

9514 1404 393

Answer:

  A

Step-by-step explanation:

The function f(x) is required in the numerator, eliminating choices C and D.

The restriction is that function g cannot be zero, so we cannot have ...

  3x +2 = 0

  3x = -2

  x = -2/3 . . . . . eliminates choice B; confirms choice A

which of the following statements is true? -6 < -8 -6> -8 or -6=-8

Answers

Answer:

-6>-8

Step-by-step explanation:

-6 is more than -8.

is jannelle correct ?

Answers

Answer:

yes

Step-by-step explanation:

o

After a large fund drive to help the Boston City Library, the following information was obtained from a random sample of contributors to the library fund. Using a 1% level of significance, test the claim that the amount contributed to the library fund is independent of ethnic group.

Number of People Making Contribution
Ethnic Group $1-50 $51-100 $101-150 $151-200 Over $200 Row Total
A 77 63 54 39 18 251
B 90 48 76 26 24 264
C 73 67 59 37 30 266
D 108 82 70 50 30 340
Column Total 348 260 259 152 102 1121

Required:
a. What is the level of significance?
b. Find the value of the chi-square statistic for the sample.
c. Find or estimate the P-value of the sample test statistic.
d. Based on your answers in parts (a) to (c), will you reject or fail to reject the null hypothesis of independence?

Answers

Answer:

α = 0.01 ; 2 - tailed

χ² = 16.998

Pvalue = 0.1497

Fail to reject H0

Step-by-step explanation:

Given the data above :

Number of People Making Contribution

Ethnic Group $1-50 $51-100 $101-150 $151-200 Over $200 Row Total

A 77 63 54 39 18 251

B 90 48 76 26 24 264

C 73 67 59 37 30 266

D 108 82 70 50 30 340

Column Total 348 260 259 152 102 1121

1.) The level of significance, α/2 = 0.01/2

2.)

The hypothesis :

H0 : Contribution and Ethnic group are independent

H1 : Contribution and Ethnic group are not independent

The Chisquare statistic :

χ² = (Observed - Expected)²/ Expected

The expected value for each cell is calculated thus :

(Row total * column total) / sum total

The expected values :

77.9197 58.2159 57.992 34.0339 22.8385

81.9554 61.231 60.9955 35.7966 24.0214

82.5763 61.6949 61.4576 36.0678 24.2034

105.549 78.8582 78.5549 46.1017 30.9367

Using the χ² formula above ;

χ² values for each cell are :

0.010855 0.393154 0.274794 0.724635 1.02509

0.789645 2.85902 3.69099 2.68108 0.0000191

1.11055 0.456179 0.098278 0.0240936 1.38826

0.056933 0.125176 0.93165 0.32963 0.028359

Taking the sum :

0.010855+0.393154+0.274794+0.724635+1.02509+0.789645+2.85902+3.69099+2.68108+0.0000191+1.11055+0.456179+0.098278+0.0240936+1.38826+0.056933+0.125176+0.93165+0.3293+0.028359

χ² = 16.998

To obtain the Pvalue :

df = (Row - 1)(column - 1) = (5-1)*(4-1) = 4 * 3 = 12

Pvalue(16.998 ; 12) = 0.1497

If Pvalue < α ; Reject H0 ;

Since Pvalue > α ; WE fail to reject H0

The value of f(x)= 5x -4x²+3 when x= -1, is​

Answers

Answer:

F(x) =5(-1)-4(-1)^2+3,

=-5-4+3

=-6

Two identical lines are graphed below. How many solutions are there to the system of equations?

A. Two
B. One
C. Zero
D. Infinitely many​

Answers

Answer:

the answer is D. infinitely many

The number of solutions there are to the system of equations is Infinitely many, the correct option is D.

What is the Point-slope form?

The equation of the straight line has its slope and given point.

If we have a non-vertical line that passes through any point(x1, y1) has gradient m. then general point (x, y) must satisfy the equation

y-y₁ = m(x-x₁)

Which is the required equation of a line in a point-slope form.

We are given that;

The two identical lines

Now,

We can find the equations of the two lines by using the slope-intercept form of a line, which is y = mx + b, where m is the slope and b is the y-intercept.

For line 1, we have two points (0,2) and (1,0), so we can find the slope as:

m1 = (0 - 2) / (1 - 0) = -2

Using point-slope form, we can write the equation of line 1 as:

y - 2 = -2(x - 0)

y = -2x + 2

For line 2, we have two points (-1,4) and (2,-2), so we can find the slope as:

m2 = (-2 - 4) / (2 - (-1)) = -2

Using point-slope form, we can write the equation of line 2 as:

y - 4 = -2(x - (-1))

y = -2x + 2

We can see that the two lines have the same slope and the same y-intercept.

Therefore, by the given slope of the line the answer will be infinitely many.

Learn more about slope here:

https://brainly.com/question/2503591

#SPJ7

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