1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
likoan [24]
3 years ago
11

The method of tree ring dating gave the following years A.D. for an archaeological excavation site. Assume that the population o

f x values has an approximately normal distribution.1229 1257 1313 1201 1268 1316 1275 1317 1275(a) Use a calculator with mean and standard deviation keys to find the sample mean year x and sample standard deviation s. (Round your answers to the nearest whole number.)x = A.D.s = yr(b) Find a 90% confidence interval for the mean of all tree ring dates from this archaeological site. (Round your answers to the nearest whole number.)lower limit A.D.upper limit A.D.

Mathematics
1 answer:
irga5000 [103]3 years ago
5 0

Answer:

1.The sample mean and standard deviation are 1272 and 40

2. The 90% confidence interval for the mean is between 1237 and 1306

Step-by-step explanation:

See attached picture for explanations.

You might be interested in
Help appreciated! (Will mark as Brainliest)
WARRIOR [948]

Answer:

trapezoid

Step-by-step explanation:

parallelograms require two sets of parallel lines while trapezoids do not, only requiring one set. it is possible to get a trapezoid with 2 90 degree angles.

3 0
2 years ago
Curtis rides his bike 9 miles one way then turns around and rides back. On the return trip, his speed is increased 20% because t
k0ka [10]

Answer:

The expression that represents his total time is given by "t = 7.5/s" where s is his speed against the wind.

Step-by-step explanation:

In order to solve this problem we will assign a variable to Curtis speed on the first leg of the trip, this will be called "s". Since the speed on the first part is "s" and the speed on the second part is 20% higher, then the speed on the second part is "1.2s". Each leg of the course is 9 miles long, therefore the time it took to go each way is given by:

time = distance/speed

First part:

t1 = 9/s

Second part:

t2 = 9/1.2s = 7.5/s

The expression for the whole course is the sum of each, so we have:

t = t1 + t2

t = 9/s + 7.5/s

t = (9 + 7.5)/s = (16.5)/s

7 0
3 years ago
Bradley completed 3/5 of his homework. What percent of his homework does he still need to complete?
Y_Kistochka [10]
1 - 3/5 = 5/5 - 3/5 = 2/5 = 0.4 = 40%
5 0
3 years ago
HELP QUITCKLY <br> combine like terms to create an equivalent expression to 8(8+7J+8).
Zinaida [17]

Answer: 56j + 128

Step-by-step explanation:

3 0
2 years ago
Read 2 more answers
Solve for k in g=k-a.​
Varvara68 [4.7K]

Answer:

k = g + a

Step-by-step explanation:

g = k - a ( add a to both sides )

g + a = k , that is

k = g + a

5 0
2 years ago
Other questions:
  • Consider the polynimial equation x(x-3)(x-6)(x-7)=0. Which of the following are zeros of the equation? Selet all that apply
    9·1 answer
  • If M(6,9) is the midpoint of the line segment AB, and if A has coordinates (3,5), find the coordinates of B.
    8·1 answer
  • PLEASE I NEED HELP! How do you find y?
    10·1 answer
  • Given two angles that measure 50 degrees and 80 degrees and side that measures 4 feet, how many triangles, if any, can be constr
    11·1 answer
  • Find the values of x and y in the figure below:
    9·2 answers
  • 18 - (-f) = 91 (With work please)
    13·2 answers
  • (CHOOSE 1 CORRECT ANSWER, VERY IMPORTANT QUIZ!!)
    8·2 answers
  • Noel has rowing lessons every 5 days and guitar lessons every 6 days. If he had both lessons on the last day of the previous mon
    10·1 answer
  • Out of the four benefits of direct deposit (safety, convenience, quick access to money, increased savings), which is the MOST co
    6·1 answer
  • Polygon angle sum theorem, solve for many points.
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!