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
Ber [7]
3 years ago
6

An ecological group suspects tuna are consuming dangerous levels of copper in a region of the world. Dangerous levels of copper

are classified when they reach beyond 5.7 parts per
million. A random sample of 21 tunas in the region were tested and the data is shown in the stemplot.
Copper Levels
20
2.
31
3578
4 01
45678
5 | 0233
5689
634
6
Key: 20 = 2.0 parts per million
Part A: What proportion of the tuna in the sample have dangerous levels of copper in their systems? (4 points)
Part B: Construct and interpret a 98% confidence interval for the mean copper levels of the tuna if the sample of 21 tuna has a mean copper level of 4.77 parts per million and standard
deviation of 11 16 parts per million. (6 points)
Mathematics
1 answer:
Mademuasel [1]3 years ago
8 0

Answer:

Step-by-step explanation:

A) From the stem-leaf plot, we see that out of 21 tunas, 5 have dangerous levels of copper since the levels go beyond 5.7 parts per million. The required proportion is 5/21=0.2381

B) Given the sample mean is {x}=4.77, sample standard deviation s=1.16 and the sample size is n=21.

Since the population standard deviation is not known, we use t-distribution.

So the 98% CI for mean is

4.77 ± t{1-0.02 /2,20} x 1.16/sqrt(21) = (4.13, 5.41)}

We are sure with 98% confidence the true copper level (in parts per million) lies in the interval (4.13, 5.41)

You might be interested in
The projected number of employed writers and authors in 2016 is 153,000. 12.4% of those will have some college experience but no
iren [92.7K]
153000 x  0.124 = 18972 employees with some college experience
153000 x 0.841 = 128673 employees with bachelor degree
128673 - 18972 = 109701 more writers and authors with bachelor's degree than just some college experience
3 0
2 years ago
What is the slope of this line?
scZoUnD [109]

Answer:

A

Step-by-step explanation:

019eheiehejeeiejehehhehe

5 0
2 years ago
Anna has made 30 chocolate chip cookies and 54 sugar cookies. She wants to put them in bags for her friends with the same number
NARA [144]

Answer:

Therefore the greatest number of cookies she can put each bag is 14.

Step-by-step explanation:

Given that Anna has made 30 chocolate chip cookies and 54 sugar cookies.

First we have to find out the number of fried or the number of bags.

So to find the number of bags, We need to find out the G.C.D of 30 and 54.

30=5×3×2

54=3×3×3×2

The common divisor of 30 and 54 is = 3×2 = 6

∴The  G.C.D of 30 and 54 is 6.

The number of bags is 6.

The number of chocolate cookies each bags is

=(The number of chocolate cookies÷ 6)

=30÷6

=5

The number of sugar cookies each bags is

=(The number of sugar cookies÷ 6)

=54÷6

=9

Therefore the greatest number of cookies she can put each bag is (5+9)=14.

5 0
3 years ago
Rebecca is a Texas resident and she plans to attend Texas Tech for all 4 years of college. She has a yearly scholarship of $10,0
andrezito [222]

Answer:

To complete the required $m dollars for her college, she needs $(m - 60,000).

Step-by-step explanation:

Suppose Rebecca needs $m to complete her college education,

because she has a yearly scholarship of $10,000, she would have $10,000 × 4 = $40,000 for the four years she would spend in college.

Together with her savings of $20,000, she has $20,000 + $40,000 = $60,000 in total.

Therefore to complete the required $m dollars for her college, she needs $(m - 60,000).

5 0
3 years ago
The temperature was 13 °F and then fell 5 degrees. What was the final temperature?
AURORKA [14]
temp is 65 degrees
6 0
2 years ago
Read 2 more answers
Other questions:
  • 12 is 50% of what number
    6·2 answers
  • There are 75 girls in a bowling league. There are three girls for every boy in the league. How many boys are in the league?
    9·1 answer
  • I attatched the problem
    13·2 answers
  • Jerry invested $14,000 in a certificate of deposit at 5%. He also put $2,500 in a savings account at 3%. How much interest will
    9·1 answer
  • The lengths of the sides of a triangle are in the extended ratio 8:9:10. The perimeter of the triangle is 54 cm. What are the le
    8·1 answer
  • Three times the measure of the supplement of an angle is 108 degrees more than 9 times the measure of the angle's complement. Fi
    9·1 answer
  • What is the name of the period that has the digits 913
    5·1 answer
  • What is the solution for x in the equation? -2x + 14 + 10x = 34 A. X=6 B. X=2/5 C. X=1/8 D. X=5/2
    12·1 answer
  • A cheetah ran 300ft in 2.92 sec what was the average speed in mph
    11·1 answer
  • PLEASE HELP PLEASE HELP PLEASE
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!