answer.
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
Evgesh-ka [11]
1 year ago
8

There is an integer n such that 2n2 − 5n + 2 is prime. To prove the statement it suffices to find a value of n such that (n, 2n2

− 5n + 2) satisfies the property "2n2 − 5n + 2 is prime." Show that you can do this by entering appropriate values for n and 2n2 − 5n + 2.
Mathematics
1 answer:
fomenos1 year ago
7 0

Answer:

n = 0 or 3

Step-by-step explanation:

2n² - 5n + 2

2n² - 4n - n + 2

2n(n - 2) -1(n - 2)

(n - 2)(2n - 1)

Prime number is one which is divisible by itself and 1

n-2 = 1 n = 3

2n-1 = 1 n = 0

You might be interested in
How do you evaluate 1.5x + 120 ≥ 270
Y_Kistochka [10]

1.5x + 120 ≥ 270

1.5x ≥ 150

x ≥ 100

5 0
1 year ago
A random sample of 160 car purchases are selected and categorized by age. The results are listed below. The age distribution of
seraphim [82]

Answer:

The claim that all ages have purchase rates proportional to their driving rates is false.

Step-by-step explanation:

The complete question is:

A random sample of 160 car accidents are selected and categorized by the age of the driver determined to be at fault. The results are listed below. The age distribution of drivers for the given categories is 18% for the under 26 group, 39% for the 26-45 group, 31% for the 45-65 group, and 12% for the group over 65. Calculate the chi-square test statistic used to test the claim that all ages have crash rates proportional to their driving rates.

Age      >26     26-45       46-65      45<

Drivers 66    39            25          30

  A) 95.431

      B)101.324

      C)85.123

      D)75.101

Solution:

In this case we need to test whether there is sufficient evidence to warrant rejection of the claim that all ages have crash rates proportional to their driving rates.

A Chi-square test for goodness of fit will be used in this case.

The hypothesis can be defined as:

<em>H₀</em>: The observed frequencies are same as the expected frequencies.

<em>Hₐ</em>: The observed frequencies are not same as the expected frequencies.

The test statistic is given as follows:

\chi^{2}=\sum{\frac{(O-E)^{2}}{E}}

The values are computed in the table.

The test statistic value is 75.10.

The degrees of freedom of the test is:

n - 1 = 4 - 1 = 3

Compute the p-value of the test as follows:

p-value < 0.00001

*Use a Chi-square table.

p-value < 0.00001 < α = 0.05.

So, the null hypothesis will be rejected at any significance level.

Thus, there is sufficient evidence to warrant rejection of the claim that ages have crash rates proportional to their driving rates.

3 0
2 years ago
Pecans that cost $28.50 per kilogram were mixed with almonds that cost $22.25 per kilogram. How many kilograms of each were used
atroni [7]

Answer:

The pecans used in the mixture =  8 kg

The almonds used in the mixture  =  17 kg

Step-by-step explanation:

The cost of per kg of pecans  = $28.50

The cost of per kg of almonds = $22.25

Now, total weight of mixture  = 25 kg

Let us assume the weight of pecans in the mixture   =   m kg

So, the amount of almonds in the mixture  = Total weight - Weight of Pecans

= (25 - m) kg

Now, cost of m kg pecans  = m x ( cost of 1 kg pecans) = m x ( $ 28.50)

                                              =  28.50 m

cost of (25- m) kg almonds  = (25 -m)  x ( cost of 1 kg almonds)

                                                = (25 - m) x ( $ 22.25)

                                                =  556.25  - 22.25 m

Total cost  of 25 kg of mixture  = 25 x ( $24.25) =  $606.25

Now, Total Cost of (almonds  + Pecans)  = Total cost of mixture

⇒28.50 m + 556.25  - 22.25 m  = $606.25

or,6.25 m =  50

or, m = 50/6.25 =  8

Hence, the pecans used in the mixture = m = 8 kg

And the  almonds used in the mixture  = (25 - m) = 25 - 8 = 17 kg

5 0
1 year ago
A Cepheid star is a type of variable star, which means its brightness is not constant. The relationship between the brightness o
White raven [17]

Answer:

The absolute brightness of the Cepheid star after a period of 45 days is -5.95

Step-by-step explanation:

Since the absolute magnitude or brightness of a Cepheid star is related to its period or length of its pulse by

M = –2.78(log P) – 1.35 where M = absolute magnitude and P = period or length of pulse.

From our question, it is given that P = 45 days.

So, M = –2.78(log P) – 1.35

M = –2.78(log 45) – 1.35

M = –2.78(1.6532) – 1.35

M = -4.60 - 1.35

M = -5.95

So, the absolute magnitude or brightness M of a Cepheid star after a period P of 45 days is -5.95

8 0
1 year ago
Read 2 more answers
Describe 59 on two other ways
AnnyKZ [126]
59 is a number
59 can be written as 59/1
6 0
2 years ago
Read 2 more answers
Other questions:
  • Will give brainliest. Given a mean of 61.2 and a standard deviation of 21.4, what is the z-score of the value 45 rounded to the
    14·2 answers
  • The table shows the precipitation in December, in inches, for Washington state from 2005 to 2013. What was the mean amount of pr
    6·2 answers
  • BRAINILEST!!!Mikel is determining if the two triangles below could be similar based on their side lengths.
    6·2 answers
  • The area of ABED is 49 square units. Given AGequals9 units and ACequals10 ​units, what fraction of the area of ACIG is represent
    5·1 answer
  • Pete’s return from selling his investment is $22,000. He had purchased the investment at a cost of $20,000. What is Pete’s retur
    11·1 answer
  • Which expression is equivalent to the following complex fraction?
    14·2 answers
  • An art teacher buys 9 bags of cotton balls there are 68 cotton balls in each bag whitch expression is best to estimate the numbe
    12·1 answer
  • Identify the domain of the function shown in the graph.
    14·1 answer
  • A person places $479 in an investment account earning an annual rate of 8.2%, compounded continuously. Using the formula V = Pe^
    13·1 answer
  • Mr and mrs Jones buy cinema tickets for themselves and their three children. the cost of an adult ticket is £6 more than a child
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!