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bobbym wrote:

Hi;

4)

You are using the right formula but your algebra is incorrect.

= 18 - 18 + x = 22 - 18

x = 3

It is supposed to be x = 4

6)

From the recurrence you get the first 6 terms.

3, 11, 35, 107, 323, 971...

iv) To plug in the formula you replace n with the numbers 0,1,2,3,4. You should get the above numbers.

First one checks.

Second one checks.

Third one checks.

Can you do the remaining two?

Thanks boby, can you please help me with the remaining. You don't have to worry about no. 7 I would still show you my answer for you to check. This is kinda frustrating because most of the questions given are not discussed in the class. I was only able to answer questions that are.
Please help me I just want to finish this course, aside from this I have other assessments that I am finishing that is why I need assistance from online resources such as this message board in regards to mathematics.

Thank you.

John E. Franklin wrote:

I'm guessing here, but maybe I'm right?!
3. a.)
threeplace Boolean Function F(x,y,z) = (3x + 2y + z) mod 2.
xyz=F
000=0
001=1
010=0
011=1
100=1
101=0
110=1
111=0
This is just guesswork by plugging in zeros and ones.
As for part b.), I don't know what the arrows are for yet.

bobbym wrote:

Hi;

I never recommend just copying answers. In math we can check things for ourselves. Yes, it is what I would put down.

iv) You have to plug in.

Plug-in? how do I plug-in? sorry english is not my first language. Can you please tell me exactly what should I do? and also can you please check if I got right answer for question 4.

bobbym wrote:

Okay, thanks for rewriting it.

2a)

2b)

5.    An athlete aims to improve her time on a given course by 1.5 seconds a day. If on the first day she runs the course in 4.25 minutes, how fast must she run it on the 21st day to stay on target?

Form the recurrence:

Run the recurrence or solve for it. a(21) = 3 minutes and 45 seconds. ( thanks again John E. Franklin )

i.    Write out the first four terms of the sequence.
ii.    Find an explicit formula.
iii.    Use this formula to find the 5th term.
iv.    Check that the formula works correctly on the first 5th terms.

Solve using the characteristic equation or generating functions or by unrolling the recurrence out.

i)

3,11,35,107,...

ii)

iii)

iv) This one you check by plugging in n = 0,1,2,3,4 into ii)

8a) No, for a connected graph to have an Euler path it must have 0 or 2 odd degree vertices. Count up the number and that will show more than 2

8b) Yes, it is possible to visit each vertex once and only once. You can prove that easily.

Please tell me, are these exact answers and can just copy it? or Do I still have to figure it out.

Question 4. I used formula sum of vertex degrees = 2x no. of edges which means 11x2 = 22

then the sum of vertex degrees is = 1+2+3+4+3+5 = 18

therefore 18+x = 2x11

= 18 - 18 + x = 22 - 18

x = 3

Did I got it right??

John E. Franklin wrote:

8. a.)  no Euler paths exist because there are too many odd number of edges at many vertices, so when you go in and out, then you are left with in, but then you get stuck there before you finish the other ones.

8. b.) yes, a Hamilton path does exist because it does in a cube, so it does even without the extra curved line.  Simply go clockwise around half of the cube and then the other way as viewed through the cube which is the same clockwise if you go to the other side, but it is against the tide of the other one, and then jump back across to the start making 4 + 4 dots.

bobbym wrote:

Hi mantastrike;

Please check problem #2. As it is written it does not make much sense.

Thanks! I'll show you my progress tonight or tomorrow.

mantastrike
Replies: 72

Thanks For All!!

## #10 Re: Help Me ! » Please help me with my math homework!! showing range, median, and mode » 2011-05-14 02:44:11

By the way I have a question...

What are the chances of getting caught for plagiarism.
Most help I get are like too advance? which I cannot figure out how they were able to answer it, therefore I have no Idea about the answer.

Is it possible if a university teacher may call me and ask where am I getting answers? And would want how I got the answer?

Is it OK to ask for help if it's homework??

for example gAr's answer is straight away an answer and I just copied... For sure it's correct. Would teacher sue me?

## #11 Re: Help Me ! » Please help me with my math homework!! showing range, median, and mode » 2011-05-14 02:01:58

coefficient of variant is not included? how do I get it??

## #12 Re: Help Me ! » Please help me with my math homework!! showing range, median, and mode » 2011-05-14 01:36:00

Yes I did, I got same answer? But how am I supposed to show workings??

## #13 Re: Help Me ! » Please help me with my math homework!! showing range, median, and mode » 2011-05-14 01:25:33

is the reverse letter E is what you call variance?
my mean is 23.2, my n = 30, how can I get that reverse E and the x?

so my E = (38-23.2)^2???????
n????????????????

so... it does not = 64.3 something

Ah how can I get this??
can you please show me this one? so I can finish this... I have no Idea how can I do this

## #14 Re: Help Me ! » Please help me with my math homework!! » 2011-05-14 01:14:39

so is my cumulative
is

1
7
7
8
10
13
16
17

Right??

## #15 Re: Help Me ! » Please help me with my math homework!! showing range, median, and mode » 2011-05-14 01:08:03

so that's why! ok it's 22.5?

Now how do I get the variance? I have no Idea what is that formula?

## #16 Re: Help Me ! » Please help me with my math homework!! showing range, median, and mode » 2011-05-14 00:56:26

I arranged it it goes like this

10,10,13,14,15,17,17,18,18,18,19,20,20,22,23,24,25,26,27,27,28,31,32,32,32,34,35,36,38

middle is 23 and 24 right?
and then 23+24/2 = "23.5"

How is my median incorrect?

## #17 Re: Help Me ! » Please help me with my math homework!! » 2011-05-14 00:52:36

a) frequency is
1
6
0
1
2
3
3
1

__
6|                [  ]
5|                [  ]
4|                [  ]
3|                [  ]
2|                [  ]           _____
1|       _____[  ]     ___[        ]  ___
|___ [____]__]__[___]____ ][___]
0  10  20  30  40  50  60 70 80 90

and my 20<30 % 5.88%
so on... 35.30%
0
5.88%
11.76%
17.65%
17.65%
5.88%

how do I get cumulative out of this?

## #18 Re: Help Me ! » Please help me with my math homework!! showing range, median, and mode » 2011-05-14 00:42:53

I got the median... I missed count... it's 23

bob the formula you gave me? what the hell is that thing?? noooooooooooooo!!

## #19 Re: Help Me ! » Please help me with my math homework!! showing range, median, and mode » 2011-05-14 00:38:05

bob bundy wrote:

hi mantastrike

Oh hi bobbym.  'Pipped me to the post again!'

a) I got my sample mean which is 696/30 = 23.2

Yes, I agree with that.

b) Range max hrs usage = 38 minimum is 10 therefore 38-10 = "18" My range is 18 right??

Whoops!  Right idea, but your subtraction is wrong!

my median is 23.5 "23 and 24" is in the middle however I am confused if I should include the duplicate numbers for example 32, 32, 32 there are 32... I still did include them, can you please tell me If it's alright?

You are right to keep all duplicates, but these are not the middle numbers.

my mode is 18 and 32 is that right? because both 18 and 32 appears 3 times is it right?

Yes

c) Now this is the confusing part getting my variance
My mean is 23.2

the formule is 1/n-1
to get N first is = sum of all numbers x (X - mean)^2

The correct formula for variance is

Thanks for the correction! PHEW!! why is my middle number incorrect? half of 30 is 15 but still... If I consider 23 as middle number the numbers left on the right side is 14 numbers left so the middle is "23.5"

## #20 Re: Help Me ! » Please help me with my math homework!! showing range, median, and mode » 2011-05-14 00:34:00

bobbym wrote:

Hi;

a) is correct.

b) Range is incorrect.

b) Median is incorrect.

b) Mode is correct. We say it is bimodal.

c) Variance is wrong. Should get an answer close to 64.3

http://www.mathsisfun.com/data/standard-deviation.html

b) how come my median is incorrect??

c) Can you please show me how you get the variance and I can take it from there. Please!!

## #21 Re: Help Me ! » Please help me with my math homework!! » 2011-05-13 23:41:48

I finished a b and c
My problem now is letter D

which is plot the cumulative distribution.

How can I get this??

## #22 Re: Help Me ! » Please help me with my math homework!! showing range, median, and mode » 2011-05-13 23:38:29

Ok,
a) I got my sample mean which is 696/30 = 23.2
b) Range max hrs usage = 38 minimum is 10 therefore 38-10 = "18" My range is 18 right??

my median is 23.5 "23 and 24" is in the middle however I am confused if I should include the duplicate numbers for example 32, 32, 32 there are 32... I still did include them, can you please tell me If it's alright?

my mode is 18 and 32 is that right? because both 18 and 32 appears 3 times is it right?

c) Now this is the confusing part getting my variance
My mean is 23.2

the formule is 1/n-1
to get N first is = sum of all numbers x (X - mean)^2

I chose 38 as my X
Which is

1/696(38-23.2)^2-1

=

1/152450.84

= 6.55949157x10^-6

What the hell??

How am I supposed to get the SD and the Coefficient of variation if the answer is like that??

## #23 Re: Help Me ! » Please help me with my math homework!! » 2011-05-13 14:00:21

I don't understand.

I'll try to do another all nighter tonight, Please be online tomorrow so you can check all my work. I just need sleep.

## #24 Re: Help Me ! » Please help me with my math homework!! » 2011-05-13 13:20:03

I don't know how to do the percentage distribution and cumulative distribution

## #25 Re: Help Me ! » Please help me with my math homework!! » 2011-05-13 13:16:48

Is my histrogram correct??
what equal class size??