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
Aloiza [94]
3 years ago
15

A car starts with a speed of 20km/ hr and accelerates at a rate of 3.4 m/s for 20 seconds. What is the final speed of the car in

km/hr?
Mathematics
1 answer:
Schach [20]3 years ago
5 0

The relevant formula that we can use in this situation is:

v = v0 + at

where v is the final velocity, v0 is the initial velocity = 20 km/hr, a is acceleration at 3.4 m/s^2 and t is time at 20 seconds

First convert v0 to m/s, v0 = 5.56 m/s

v = 5.56 m/s + 3.4 m/s^2 * 20 s

v = 73.56 m/s

Then convert back to km/hr:

<span>v = 264.82 km/hr</span>

You might be interested in
last week you sold 30,45,50,75 and 80 units each day of the week in that order . On average how many units did you sell per day?
Butoxors [25]

Answer:

56 units

Step-by-step explanation:

add all numbers then divide by 5

30+45+50+75+80 = 280

280/5 = 56

4 0
3 years ago
Required information An article presents a new method for timing traffic signals in heavily traveled intersections. The effectiv
Natasha2012 [34]

Answer:

652.6-2.01\frac{311.7}{\sqrt{50}}=563.997    

652.6+2.01\frac{311.7}{\sqrt{50}}=741.203    

So on this case the 95% confidence interval would be given by (563.997;741.203)    

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

\bar X=652.6 represent the sample mean for the sample  

\mu population mean (variable of interest)

s=311.7 represent the sample standard deviation

n=50 represent the sample size  

Soltuion to the problem

The confidence interval for the mean is given by the following formula:

\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}   (1)

In order to calculate the critical value t_{\alpha/2} we need to find first the degrees of freedom, given by:

df=n-1=50-1=49

Since the Confidence is 0.95 or 95%, the value of \alpha=0.05 and \alpha/2 =0.025, and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.025,49)".And we see that t_{\alpha/2}=2.01

Now we have everything in order to replace into formula (1):

652.6-2.01\frac{311.7}{\sqrt{50}}=563.997    

652.6+2.01\frac{311.7}{\sqrt{50}}=741.203    

So on this case the 95% confidence interval would be given by (563.997;741.203)    

6 0
3 years ago
when a cannonball is fired, the equation of its pathway can be modeled by h=-16t squared + 128t. find the time it will take for
Rashid [163]
At the time the cannonball reaches the ground, the vertical height of the cannonball from the ground is 0, i.e. h = 0.

Thus, the time it will take the cannonball to reach the ground is given by

-16t^2+128t=0 \\  \\ \Rightarrow t(-16t+128)=0 \\  \\ \Rightarrow t=0\ or\ -16t+128=0 \\  \\ \Rightarrow16t=128 \\  \\ \Rightarrow t= \frac{128}{16} =8

Therefore, it will take the cannonball 8 seconds to reach the ground.
5 0
3 years ago
Jillian’s school is selling tickets for a play. The tickets cost $10.50 for adults and $3.75 for students. The ticket sales for
Gnoma [55]

Answer:

168

Step-by-step explanation:

you would times 3.75 by 82 and subtract the answer from 2071.50 and get 1764 then divide 1764 by 10.50 and get 168

3 0
3 years ago
Read 2 more answers
4768 x 1551<br> divided by 10.2
balandron [24]
4768 x 1551 is 7395168
7395168 divided by 10.2 is 725016.5 (rounded to the nearest tenths)
3 0
3 years ago
Read 2 more answers
Other questions:
  • keith ran in a marathon . it took him 3 hours and 2 minutes to run 26 miles . if he ran at the same rate for the whole race , ho
    15·1 answer
  • Cal's go cart has a gas tank with the dimensions shown below. He uses a gas can that holds 1 liter of gas, to fill the go cart t
    8·1 answer
  • A soccer player scores three goals in two games how many goals are they expected to score in nine games
    8·1 answer
  • Homework Progress
    6·2 answers
  • Help me out plzzz???!
    9·1 answer
  • I want to know what is the answer to this?
    5·1 answer
  • Someone help me please
    11·1 answer
  • What will the annual property rates be for one year if a property is worth R250 000 and if 0,989c is the property value (per yea
    10·2 answers
  • A researcher initially plans to take an SRS of size 160 from a certain population and calculate the sample mean. Later, the rese
    10·1 answer
  • Simplify 3(x-y)+3x+2<br>​
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!