the sum of the first n terms of an arithmetic sequence is 242. If the first term is 12 and the last term is 42, find the value of n

badly need this rn ​

Answers

Answer 1

Answer:

Step-by-step explanation:

Sum of first n terms = 243

[tex]a_{1} = 12 \\\\l = 42\\\\S_{n} = \dfrac{n}{2}(a_{1}+l)\\\\\dfrac{n}{2}(12+42) = 243\\\\\\\dfrac{n}{2}*54=243\\\\\\n*27=243\\\\n=\dfrac{243}{27}\\\\n=9[/tex]


Related Questions

2x+3-3=-6



x=3 ? Solve

Answers

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

[tex]x\neq 3[/tex]

As we can see, x cannot be equal to 3 as 6 cannot equal -6.

I hope I've helped! :)

What is 11 divided by 1/4

Answers

44 i think if not really sorry

PLEASE HELP GIVING BRAINLIEST

Answers

Answer:

A.10,4

B.5,10

C.5,5

D4,4

Step-by-step explanation:

KERE ON LERNER?

For constant term: f(a,b,g(t)), pattern term: f(a,Y,X) when pattern matching we can use the following assignment Y=b and X=g(t) to make the two terms match.

Note: A variable in the pattern is allowed to match anything in the other structure.

What do the uppercase letters X,Y represent?

Answers

Answer:

fuctions and constants

Step-by-step explanation:

please mark as brainliest if it helped :D

Which choice is equivalent to the expression below?

5 SQR7-4x SQR7-xSQR7

A. 0
B.-2xSQR7
C.-X^2
D. 5 SQR 7 -5xSQR7

Answers

I think is the B, tell me if it's correct OK i'm trying to help

Answer:

5√7-5x√7

Step-by-step explanation:

Consider the following data to determine whether there is a significant difference between the values of Group 1 and Group 2. Let the significance level be 5%. Group 1: 15, 17, 26, 11, 18, 21, 13, 29 Group 2: 23, 14, 24, 13, 22, 23, 18, 21 What rank will be given to the value 15

Answers

Using the t-distribution, it is found that since the p-value of the test is 0.72 > 0.05, there is not significant difference between the values of each group.

At the null hypothesis, we test if the groups have the same values, that is, the subtraction of their means is 0:

[tex]H_0: \mu_2 - \mu_1 = 0[/tex]

At the alternative hypothesis, we test if the groups have different values, that is, the subtraction of their means is different of 0:

[tex]H_1: \mu_2 - \mu_1 \neq 0[/tex]

First, we have to find the mean and the standard deviation for both samples, hence, using a calculator:

[tex]\mu_1 = 18.75, \sigma_1 = 6.2507, \mu_2 = 19.75, \sigma_2 = 4.2678[/tex]

The standard errors are:

[tex]s_1 = \frac{\sigma_1}{\sqrt{n_1}} = \frac{6.2507}{\sqrt{8}} = 2.21[/tex]

[tex]s_2 = \frac{\sigma_2}{\sqrt{n_2}} = \frac{4.2678}{\sqrt{8}} = 1.5089[/tex]

For the distribution of differences, we have that:

[tex]\overline{x} = \mu_2 - \mu_1 = 19.75 - 18.75 = 1[/tex]

[tex]s = \sqrt{s_1^2 + s_2^2} = \sqrt{2.21^2 + 1.5089^2} = 2.676[/tex]

We have the standard deviation for the samples, hence, the t-distribution is used. The test statistic is given by:

[tex]t = \frac{\overline{x} - \mu}{s}[/tex]

In which [tex]\mu[/tex] is the value tested at the null hypothesis, which is 0 for this problem. Hence, the value of the test statistic is:

[tex]t = \frac{\overline{x} - \mu}{s}[/tex]

[tex]t = \frac{1 - 0}{2.676}[/tex]

[tex]t = 0.37[/tex]

To find the p-value, we have a two-tailed test, as we test if the means are different from a value, with t = 0.37 and 8 + 8 - 2 = 14 df.

Using a t-distribution calculator, this p-value is of 0.72.

Since the p-value of the test is 0.72 > 0.05, there is not significant difference between the values of each group.

A similar problem is given at https://brainly.com/question/15682365

Can someone check my work?

Answers

Answer:

See below:

Step-by-step explanation:

Hello! My name is Galaxy and I will be helping you today!

We can check your answer in 1 step.

We need to find how much they earn if they worked 37 hours at a rate of 26 dollars per hour.

We can mutliply to figure this out:

[tex]37*26=962[/tex]

Therefore, yes, your answer is correct!

Cheers!

Answer:

$26=1hr

x   =37hr

$26 x 37=$ 962

Step-by-step explanation:

9.2 less than 3 times a number is the same as 21 1/4

Answers

Answer:

10.15

Step-by-step explanation:

3x-9.2 = 21.25

3x = 30.45

x = 10.15

Answer:

10.15

Step-by-step explanation:

I took the K12 test

What is the value of y in y = 2x - 5, when x = 3.9?

Answers

Answer:

Y = -3 and with x as 3.9 y equals 2.8

Step-by-step explanation:

what is the equation of the line that is perpendicular to y=-1/4x-2 and goes through the point (-2,-3)

Answers

Step-by-step explanation:

y=-1/4x-2

1/4x+y+2=0.........1

line perpendicular to eqn 1 is

x-1/4y+k=0

as the line passes through the (-2,-3)

-2-1/4×-3+k=0

-1+4k=0

K=1/4

the eqn is 4x-y+1=0

Can someone tel me if the answers are correct ? Please

Answers

Answer:

huuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuh

Which is an x-intercept of the graph of the

Answers

Answer:

(5π/8, 0)

Step-by-step explanation:

x intercept occurs when y = 0

0 = tan(x - 5π/8)

as tan0 = 0

x - 5π/8 = 0

x = 5π/8

using the rectangle below calculate the values of x and y

Answers

Answer:

x=4, y=9/7

Step-by-step explanation:

We will use the property that the opposite sides of a rectangle are equal

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

9y-3=2y+6

7y=9

y=9/7

2x=4(x-2)

2x=4x-8

2x=8

x=4

Suppose that the radius of a sphere is divided by 9. What happens with the surface area?

Answers

Answer:

Rad/9

Step-by-step explanation:

What is the perimeter of a rectangle with a length of 11.25 inches and a
width of 8 inches?

Answers

Answer:

38.5 in

Step-by-step explanation:

11.25 in + 11.25 in + 8 in + 8 in

= 38.5 in

Fireworks are fired from the roof of a 100-foot building and travel 84 feet per second. The equation h = -16t 2 + 84t + 100 models the height h of the fireworks at any given time t seconds.

Answers

The firework reaches the ground after 6.25 seconds.

A projectile is the curved motion of an object thrown into space under the influence of gravity.

Given that the firework experiences a projectile motion given by the equation:

h = -16t² + 84t + 100

where h is the height after t seconds.

The firework reaches the ground when h = 0, hence:

0 = -16t² + 84t + 100

t = 6.25 seconds.

Therefore the firework reaches the ground after 6.25 seconds.

Find out more at: https://brainly.com/question/11422992

What Value is equivalent to 30-6 x 3

Answers

Answer:

5/1

Step-by-step explanation: I could be wrong though

Have a Good Day <3

5/1 this should be right

Find the exact value of the expression below
Sec 30degrees Cos 30degrees - tan 60degrees cot 60degrees ​

Answers

Answer:

0

Step-by-step explanation:

1×2÷√(3)×√(3)÷2 - √(3)×1÷√(3)

1-1

0

for more refer to the image

Reasoning if you know one angle measure of a parallelogram, how do you find the other three angle measures? Explain. ​

Answers

To find the other angles in a parallelogram if only one is given then you need to subtract the number with 180 to find the consecutive angles. With the theorem 6-5 opposite angles are congruent, so the opposite side would have the same value.

Write the equation of the line passing through (-2, 1) and parallel to the line whose equation
is y = 2x + 1. Express the equation in point-slope form and slope-intercept form.

Answers

Answer: y=2x+1 (slope intercept form) & y-1=2(x+2) (point slope form)

Step-by-step explanation:

Parallel means the m value or slope are equal

Given those points and the slope you can begin to write the slope y intercept form

y=2x+B

Solve B or Y intercept x=0 and the Y value we get from the given points.

1=2*0+B

y=2x+1 (slope intercept form)

for point slope plug the points in this equation

y-y1=m(x1-x1)

y-1=2(x+2) (point slope form)

sara buys two bags of chips and three boxes of pretzels for $ 85. He then buys another bag of chips and two more boxes of pretzels for $ 50. Find the cost of each bag of chips and each box of pretzels.

Answers

Answer:

Chips= $20    Pretzel=$15

Step-by-step explanation:

Sara bought 2 Chips + 3 Pretzels = $85

(Extra) 1 Chips + 2 Pretzels = $50

Pretzels are twice as much as chips so above ^^ Can be expressed

as Pretzel (15) + Pretzel (15) + Chips(20) = $50

Now lets go back to the first line Putting in the new prices

Chips(20) + Chips(20) + Pretzel(15) + Pretzel(15) = Pretzel(15) = $85

Name one problem-solving strategy and briefly describe how it can help you as a problem-solver.?

Answers

Answer:

Trial and error

Step-by-step explanation:

It can help you by testing mulitple solutions to decleare which one is best.

how many ten thousand are in 1,000,000?​

Answers

Answer:

100

Step-by-step explanation:

10,000 * 100 = 1,000,000

So there are 100 ten thousands in 1,000,000

Two of the angles in a triangle measure 58 degrees and 25 degrees. What must be the measure of the third angle?

Answers

97 degrees

add up the two and subtract by 180

Solve the equation for x:
x2 = 196

Answers

Answer: x= 1/196

Step-by-step explanation:

A motor that’s rated at 1/8 horsepower is used to drive a pump. How much horsepower will be applied to the pump if the motor delivers only 2/7 of its rated horsepower?
A. 23/56
B. 1/28
C. 2/15
D.7/16

Answers

Based on the information given, the fraction of horsepower that will be applied to the pump will be 1l28.

From the information given, it can be seen that the motor is rated at 1/8 horsepower and used to drive a pump.

Therefore, the fraction of the horsepower that will be applied to the pump if the motor delivers only 2/7 of its rated horsepower will be:

= 2/7 × 1/8.

= 2/56

= 1/28

Learn more about fraction on:

https://brainly.com/question/25803541

Can someone please help me I will mark u brilliant

Answers

Answer:

the correct answer is 7/20

Find the additive inverse and the multiplicative inverse, if it exists, of the given number. 5 in modulo 8 arithmetic

Answers

The additive inverse of 5 modulo 8 is the number a such that

5 + a ≡ 0 (mod 8)

Then

a ≡ -5 ≡ -5 + 8 ≡ 3 (mod 8)

The multiplicative inverse is m such that

5m ≡ 1 (mod 8)

Use the Euclidean algorithm:

8 = 1•5 + 3

5 = 1•3 + 2

3 = 1•2 + 1

Then

1 = 3 - 1•2

1 = 3 - 1•(5 - 1•3) = 2•3 - 1•5

1 = 2•(8 - 1•5) - 1•5 = 2•8 - 3•5

and so

1 ≡ 2•8 - 3•5 ≡ (-3)•5 (mod 8)

which means the inverse of 5 is

-3 ≡ 8 - 3 ≡ 5 (mod 8)

F=8
e=0.2
When F=25 find x

Answers

Answer:

0.625

Step-by-step explanation:

hope it can help you lovelots

Tom is reviewing his cell phone bill. When he gets to the text message part he notices that he send 1 text message in October,7 text messages in November, 49 messages in December,and 343 text messages in January. what kind of sequence is this?
a. arithmetic b. geometric c. both d. neither​

Answers

Answer:

it is c. both i guess anyways thanks

i hope you passed and sorry for taking your points

Step-by-step explanation:

Other Questions
your computer records the raw sequencing data shown below. how many different sequences are represented in this dataset? the similarity between a poem and a dialogue At a school Number of boys : number of girls 11:9There are 124 boys than girlsWork out the total amount of students at the school What is the constant of proportional for y=3/4x his drummer's activity was conversation-like and his fills were melodic like the horns they complimented. a. Philly Joe Jones b. Art Blakey c. Max Roach d. Elvin Jones Find the value of x and y help me please need this right now In what ways does dehumanization play a role in this reading? Explain and give an example from the readingthe link will be in the comments I need help on 40 please Please help, I will give Brainliest to the best answer.What was the Columbian Exchange?DEFINITION:Item Negative or positive impact? Why?Disease: Horses: Cattle, Pigs, Chickens: Guns: Cash Crops: How did this Impact Native Americans?Population Decline:Land: Peaceful Coexistence: helpppp please!!!!!!! Assume that a randomly selected subject is given a bone density test. Those test scores are normally distributed with a mean of 0 and a standard deviation of 1. Draw a graph and find the probability of a bone density test score greater than 1.66. !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!9 Bonie reduced the size of a photo to a height of 4 in. what is the new width if it was orginally 16 in tall and 8 in wide? what is the first step in solving problem using GMDAS? Given: SR is the perpendicular bisector of QT; QR is the perpendicular bisector of SPProve: PQ=TS When we round 7.80576 to 3s f, it is equal to: During the time that Harriet Jacobs lived in an attic crawl space for seven years, and could not contact her children--what do you think she was going through? For this assignment, write a creative written response that reflects your understanding of the text excerpts that we read. (Some suggestions--a letter from Harriet to her children; a monologue; a poem. 1st person--I/we--writing is acceptable here.) Write this response below. The following balanced equation shows the formation of water. 2H2 O2 2H2O How many moles of oxygen (O2) are required to react completely with 1. 67 mol H2? 0. 835 mol O2 1. 67 mol O2 3. 34 mol O2. 4. Find a value of x that is a solution to 5(x - 3) = x + 13. Describe how you found the solution Tim Worker wants to purchase an automobile warranty costing $6,659.If he chooses to make 48 equal payments, then in dollars and cents the average payment will be $_____