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
kykrilka [37]
3 years ago
5

It takes 36 minutes less time to travel 120 miles by car at night than by day because the lack of traffic allows the average spe

ed at night to be 10 miles per hour faster than the daytime. Find the average speed in the daytime.
Mathematics
1 answer:
denpristay [2]3 years ago
8 0
Let the average speed at day time be x miles per hour

Therefore at night the average speed = (x + 10) miles per hour

Time = Distance / speed

Time at day  -  Time at night =  36 minutes.

36 minutes = 36/60 hour =  6/10 hour

Time at day = Distance / speed at day =  120 / x

Time at night = Distance / speed at night =  120 / (x + 10)


  120/x   -  120/(x + 10) = 6/10

     1/x  -  1/(x + 10)  =  6/10* 1/120

       1/x -  1/(x + 10) =  1/200

         ((x + 10) - x) / ((x)(x+10)) = 1/200

             (x + 10 - x) / ((x)*(x+10)) = 1/200

                     10 / ((x)*(x + 10)) = 1/200

                         1 / ((x)*(x + 10)) = 1/2000

   Therefore        x (x + 10) =  2000

           x and x +10      are          40 and 50.    Because 40*50 = 2000

           x = 40

     Average speed in the day time = 40 miles per hour
You might be interested in
In​ 1990, the average math SAT score for students at one school was 498. Five years​ later, a teacher wants to perform a hypothe
mojhsa [17]

Answer:

A. Fail to reject the claim that the average math SAT score is 498 when in fact it is not 498.

Step-by-step explanation:

Type II Error:

A type II error happens when there is a non-rejection of a false null hypothesis.

In this question:

The null hypothesis is H0​:μ=498.

Since there is a type II error, there was a failure to reject the claim that the average math SAT score is 498 when in fact it is not 498, and thus, the correct answer is given by option A.

6 0
3 years ago
Slope = 1.75; (10, 16.5)
vazorg [7]
Do you want the equation of the line given the slope and a point it goes through?

y - y1 = m (x - x1)
y - 16.5 = 1.75 (x - 10)
y - 16.5 = 1.75x -17.5
y = 1.75x - 1
8 0
3 years ago
Please answer quickly!!!
Ivenika [448]

Answer:

3.5 min

Step-by-step explanation:

5 0
3 years ago
Solve for x and y.
Rus_ich [418]

y is 8\sqrt{3}. This is because in a 30-60-90 triangle, the side facing the 30° is always half of the side facing the 90°


x is always √3 times y, so x=24. Therefore, the answer is the second answer choice.


5 0
3 years ago
Read 2 more answers
A gumball machine has different flavors sour apple,grape,orange and cherry . There are six of each flavor. $.50 are put in the m
tamaranim1 [39]

Answer:

30/552

Step-by-step explanation:

In order to solve this problem you need to multiply the probability of getting grape for the first gumball with the probability of getting grape for the second gumball. Since there are 6 grape gumballs and a total of 24 gumballs (6*4). Then the probability of getting grape for the firs one is

\frac{6}{24}

Now there are only 5 grape gumballs available and one less in the total supply, therefore the probability of getting grape in the second try is

\frac{5}{23}

Finally we multiply them together to find the probability of getting two grapes in a row.

\frac{6*5}{24*23} = \frac{30}{552}

4 0
3 years ago
Other questions:
  • Derek bought 4 pounds of tomatoes at the grocery store. This included grape, roma, and plum tomatoes. If Derek bought 2 pounds o
    10·2 answers
  • Which equation shows an example of the associative property of addition? (–7 + i) + 7i = –7 + (i + 7i) (–7 + i) + 7i = 7i + (–7i
    14·2 answers
  • Which choice shows the best estimate of the product 0.48×591
    13·2 answers
  • The length of a rectangler picture is 5 inches more than three times the width find the dimensions of the picture if its perimet
    12·1 answer
  • 1. In a class of students the ratio of the number of students who like to play football and the number of students who like to p
    7·1 answer
  • Carmen is recording the number of points she misses on each math quiz. Here are her results for the lastnine quizzes
    14·1 answer
  • Daniel wants to buy cookies for her friend. The
    13·2 answers
  • How many posters and picture frames does the store sell on that day?
    6·1 answer
  • I need Help...........
    5·1 answer
  • Solve for k:<br> 8 36<br> K 1.8
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!