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
Anna007 [38]
3 years ago
6

A boat traveled 189 miles downstream and back. The downstream trip took 7 hours. The trip back took 21 hours. Find the speed of

the boat in still water and the current.
Mathematics
1 answer:
SSSSS [86.1K]3 years ago
5 0
 7hrs/ =x
21hrs 189
1323=7x
7       7
189=x
the speed of the boat in still water is 189
i got the answer by setting a proportion.
hope it work
You might be interested in
(x² y³ z)⁴ simplified
dexar [7]

Answer:

7 x² y z⁴  =  7 ⋅ x² ⋅ y ⋅ z³ ⋅ z

21 x² y⁵ z³ = 7 ⋅ 3 ⋅ x² ⋅ y ⋅ y⁴ ⋅ z³

Step-by-step explanation:

8 0
3 years ago
Read 2 more answers
I need help on this​
charle [14.2K]

Answer:

20.33 is the answer pls follow me and make my answer as brainlist

5 0
3 years ago
5 divided by 39.5 please awnser
adell [148]
the answer to 5 divided by 39.5 is 0.127
6 0
3 years ago
Calculeaza aria unu paralelogram cu latura 3 radical 2 cm si inaltimea 2cm
zloy xaker [14]

Answer:

Aria unui paralelogram =6\sqrt{2}

Step-by-step explanation:

Folosind formula:

Aria unui paralelogram = (baza x înălțimea)

                                       = (3√2 x 2)

                                        =6\sqrt{2}

Aria unui paralelogram =6\sqrt{2}

6 0
3 years ago
Researchers are investigating the effectiveness of leg-strength training on cycling performance. A sample of 7 men will be selec
ruslelena [56]

Answer:

A. The interval will be narrower if 15 men are used in the sample.

Step-by-step explanation:

Hello!

When all other things remain the same, which of the following statements about the width of the interval is correct?

A. The interval will be narrower if 15 men are used in the sample.

B. The interval will be wider if 15 men are used in the sample.

C. The interval will be narrower if 5 men are used in the sample.

D. The interval will be narrower if the level is increased to 99% confidence.

E. The interval will be wider if the level is decreased to 90% confidence.

Consider that the variable of interest "Xd: Difference between the peak power of a cyclist before training and after training" has a normal distribution. To construct the confidence interval for the population mean of the difference you have to use a pooled t-test.

The general structure for the CI is "point estimate"±" margin fo error"

Any modification to the sample size, sample variance and/or the confidence level affect the length of the interval (amplitude) and the margin of error (semiamplitude)

The margin of error of the interval is:

d= t_{n-1;1-\alpha /2} * (Sd/n)

1) The sample size changes, all other terms of the interval stay the same.

As you can see the margin of error and the sample size (n) have an indirect relationship. This means, that when the sample size increases, the semiamplitude decreases, and when the sample size decreases, the semiamplitude increases.

↓d= t_{n-1;1-\alpha /2} * (Sd/↑n)

↑d= t_{n-1;1-\alpha /2} * (Sd/↓n)

Correct option: A. The interval will be narrower if 15 men are used in the sample.

2) The confidence level has a direct relationship with the semiamplitude of the interval, this means that when the confidence level increases, so do the semiamplitude, and if the level decreases, so do the semiamplitude:

↓d= ↓t_{n-1;1-\alpha /2} * (Sd/n)

↑d= ↑t_{n-1;1-\alpha /2} * (Sd/n)

I hope it helps!

4 0
3 years ago
Other questions:
  • Help please the questions are in the pictures
    10·1 answer
  • The height of a tree at time t is given by a twice-differentiable function H, where H(t) is measured in meters and t is measured
    5·2 answers
  • Y/7 =2/x do those show direct variation ​
    15·1 answer
  • The difference of the range and the interquartile range of the data set represented by the box plot is
    11·2 answers
  • Michelle leaves her house at 5:20 Am To Get To Work, Which is 20 miles away. If she drives 40 miles an hour, what time will she
    5·2 answers
  • Really easy for high schoolers (The first correct answer gets brainliest! )
    13·1 answer
  • One number is 3 less than a second number. Twice the second number is 9 more than 5 times the first
    12·1 answer
  • Find the value of x and y:
    6·1 answer
  • Given g(x)=-4x+4g(x)=−4x+4, find g(3)
    12·2 answers
  • All 136 students in the Math Club went on a field trip. Some students rode in vans which hold 8
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!