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
BaLLatris [955]
3 years ago
12

Pls help with question 4

Mathematics
1 answer:
Ksju [112]3 years ago
7 0

Answer:

C.)

Step-by-step explanation:

You might be interested in
The stopping distance d of an automobile is directly proportional to the square of its speed s. On one road, a car requires 75 f
Anton [14]

Answer:

The car requires 192 feet to stop from a speed of 48 miles per hour on the same road

Step-by-step explanation:

  • Direct proportion means that two quantities increase or decrease in the same ratio
  • If y is directly proportional to x (y ∝ x) , then \frac{y_{1}}{y_{2}}=\frac{x_{1}}{x_{2}}  <em>OR</em>  y = k x, where k is the constant of proportionality

∵ The stopping distance d of an automobile is directly

   proportional to the square of its speed s

- That means d ∝ s²

∴  \frac{d_{1}}{d_{2}}=\frac{(s_{1})^{2}}{(s_{2})^{2}}

∵ A car requires 75 feet to stop from a speed of 30 miles per hour

∴ d = 75 feet

∴ s = 30 miles/hour

- Change the mile to feet

∵ 1 mile = 5280 feet

∴ 30 miles/hour = 30 × 5280 = 158400 feet/hour

∵  The car require to stop from a speed of 48 miles per hour

    on the same road

- Change the mile to feet

∴ 48 miles/hour = 48 × 5280 = 253440 feet/hour

∵  \frac{d_{1}}{d_{2}}=\frac{(s_{1})^{2}}{(s_{2})^{2}}

- Substitute the values of d_{1} by 75 feet, s_{1} by 158400 feet/hour

   and s_{2} by 253440 feet/hour

∴ \frac{75}{d_{2}}=\frac{(158400)^{2}}{(253440)^{2}}

∴  \frac{75}{d_{2}}=\frac{25}{64}

- By using cross multiplication

∴ 25 × d_{2} = 75 × 64

- Divide both sides by 25

∴ d_{2}  = 192 feet

The car requires 192 feet to stop from a speed of 48 miles per hour on the same road

4 0
2 years ago
A student researcher compares the heights of men and women from the student body of a certain college in order to estimate the d
maria [59]

Answer:

(0.6613, 8.3387)

Step-by-step explanation:

Let the heights of men be the first population and the heights of women be the second population. Then

We have n_{1} = 15, \bar{x}_{1} = 69.4, s_{1} = 3.09 and

n_{2} = 7, \bar{x}_{2} = 64.9, s_{2} = 2.58. The pooled

estimate is given by  

s_{p}^{2} = \frac{(n_{1}-1)s_{1}^{2}+(n_{2}-1)s_{2}^{2}}{n_{1}+n_{2}-2} = \frac{(15-1)(3.09)^{2}+(7-1)(2.58)^{2}}{15+7-2} = 8.68

The 99% confidence interval for the true mean difference between the mean height of the men and the mean height of the women is given by (if the samples are independent)

(\bar{x}_{1}-\bar{x}_{2})\pm t_{0.01/2}s_{p}\sqrt{\frac{1}{15}+\frac{1}{7}}, i.e.,

(69.4-64.9)\pm t_{0.005}2.946\sqrt{\frac{1}{15}+\frac{1}{7}}

where t_{0.005} is the 0.5th quantile of the t distribution with (15+7-2) = 20 degrees of freedom. So  

4.5\pm(-2.845)(2.946)(0.458), i.e.,

(0.6613, 8.3387)

5 0
3 years ago
How do you do this geometry problem
shtirl [24]
W= 79 brooooooooooooooooooo
4 0
3 years ago
Pls help me with my homework
timofeeve [1]
Yes I worked it in my brain hahahahahah
4 0
2 years ago
Solve for x..........
-BARSIC- [3]

9514 1404 393

Answer:

  x = -9

Step-by-step explanation:

Segment NL is twice the length of midsegment WV.

  2WV = NL

  2(x+15) = x+21

  2x +30 = x +21 . . . . simplify

  x = -9 . . . . . . . . . . . . add -30-x

_____

<em>Additional comment</em>

This value of x means the other segments are ...

  MN = 12

  WV = 6

  NL = 12

5 0
2 years ago
Other questions:
  • The slope-intercept form of the equation of a line that passes through point (–3, 8) is y = –2/3x + 6. What is the point-slope f
    11·1 answer
  • Nth term of this sequence 5 10 15 20 25
    7·1 answer
  • Find the values of x and y
    11·1 answer
  • Solve for x. while you solve it can you show work pls
    7·1 answer
  • PLS HELP THANK UUU!!!
    11·1 answer
  • Does the point (5 6) satisfy the equation y = 2x - 7
    13·1 answer
  • Kevin cut a plank a yard long. He painted 1/3 yard of the plank in black. How much of the plank is unpainted?
    6·1 answer
  • What are some examples from science and engineering where a quadratic is used but is not a function?
    8·1 answer
  • A dog is on the ground watching a cat on a 6-foot-
    11·1 answer
  • Translate the sentence into an inequality.
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!