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Math / Science

The Math / Science topic primarily includes discussions of mathematics, physics, statistics and economic analysis, but also biology, chemistry and other sciences.

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For a number sequence A: (1, 2, 3, 4, 5, 6, 7, 8, 9, 10)

Are the terms in the subset B: (1, 4, 7, 8) considered in sequence given that some numbers from A were skipped?

Should I use the adjective sequential or succedent, or is there a better word?
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Become a CompTIA Certified Healthcare IT Tech
LVL 12
Become a CompTIA Certified Healthcare IT Tech

This course will help prep you to earn the CompTIA Healthcare IT Technician certification showing that you have the knowledge and skills needed to succeed in installing, managing, and troubleshooting IT systems in medical and clinical settings.

Micheal has 16.25 $ in the bank. He needs 108 $ to buy a video game. He finds he can save 1.75 $ a week from his allowance. How many weeks must he save in order to have enough to buy the game.
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Jenny has pennies , nickels , dimes , quarters , half dollars and/or dollar in her purse. still shes unable to make change for aa old two dollar bill.what is the greatsest amount of money she could possibly have.(She may have none of some of the coins.)

Barb has five small chains of three links each. She wants to make them into one long chain of 15 links. If cutting a link costs 20 cents and wedling a link costs 1.50$ what is the least cost of making the chain (Hint: You can do it for less than 6.80$.

Stefan is working on his garden. All of the flowers in the garden were white expect two,all are red except two and all are yellow except two. How many flowers are in stefan's garden.

in how many ways can change be made for for 85 cents using nothing but but nickels and/or dimes
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Hello,

I never tire of asking me: To be a good programmer, what is the relevance of getting a degree in computer science? And a good programmer has in mind all the commands of a programming language, like PHP or JAVA? The oldest languages (MSDOS) had less than 200 commands and functions, currently they must have more than 1000

I would like to hearing from you

sincerely
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The demand of IT service is a random variable (X) having the Poisson distribution μ=3.4. The cost of producing each pizza is 20 and each is sold at selling price of 40.
Suppose 5 pizza are made daily, no pizza is reserved for next day. Find the expected total profit daily.

p(0) x -100 + p(1) x -60 + p(2) x -20 + p(3) x 20 + p(4) x 40 + p(>=5) x 100

My answer = 27.1004. Suggest ans = 27.118.

Do I miss anything ?
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Consider a binomial random variable X ~ Bi(n,∅).

We can get P(x) and P(x+1) as below but how to solve question 1 & 2 ?

P(x) = nCx . ∅ x (1- ∅)n-x
p(x+1) = nC x+1 . ∅ x-1 (1- ∅) n- (x+1)
                     
Thx.
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Dear experts,

I was looking at videos which complement Good notes 4. I can came across the one below:
https://www.youtube.com/watch?v=jOG48N5U6CE&t=8s


The presenter is discussing, at time scale 8m  32sec, an app where i could write math formulae (not using key board) on an app and it calculated the result.
I have my Itunes account with country as India. I do not think it is available for India Itunes account.

I use good notes for writing my MAth theorems from Real analysis, measure and integration, number theory, linear algebra, vector spaces, ODE/PDE, probability.

Kindly can anyone provide me a list of similar apps ranked by preference.

I will then look for those which are available for India.

Kindly guide.me.

Thank you
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What is the date today if april 29 was nine days before two days after three days preceding the day before five days following the day before yesterday?

Ray and a friend drive from vancouver to toronto in 56 h of steady driving, They leave vancouver on may 30 8 am when do they arrive in toronto
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I'm wondering if the following makes sense to define the sequence of points that make up the shapes? Not sure of the proper way to describe the sequence so any help to improve the formula will be appreciated. A289006 relates to the number sequence at oeis.org. Thanks.

shape sequence Fibonacci numbers x A289006
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I've having trouble with a rounding routine in Excel.  The goal is when the user enters a number with the wrong number of significant digits, the macro rounds the number and replaces what they entered.  It does not merely change the cell display to show the desired number of digits, it actually corrects the number entered and updates the cell.

I am seeing some very strange results where sometimes the macro works and other times it does not.  Please enter the code below in a blank Excel workbook and try this out.
Private Sub Worksheet_Change(ByVal target As Range)

If target.Cells.Count > 1 Then Exit Sub

If target.Value = "" Then Exit Sub

If Not (IsNumeric(target)) Then
    MsgBox "please enter a number"
    target.Value = ""
    target.Select
    Exit Sub
End If

Call roundit(target, 0.1)

End Sub

Sub roundit(ByVal target As Range, rez As Single)

Dim x As Single

Application.EnableEvents = False

Select Case rez
Case 0.1
    x = Round(target * 10, 0) / 10
    target.NumberFormat = "0.0"
    MsgBox "Rounded value of " & target & " to the nearest " & rez & " is " & x
    target = x
End Select

Application.EnableEvents = True

End Sub

Open in new window

Try entering these test values:

5 - works
5.54 - correctly changes to 5.5
5.45 - appears to work, but the number in the cell is now 5.40000009536743
5.454545 - correctly changes to 5.5
5.656565 - appears to work, but the number in the cell is now 5.69999980926513
6.899 - appears to work, but the number in the cell is now 6.90000009536743
Etc.  I can't find the pattern!

I've got a number of possible rounding values, hence the select case, but for this example I have just provided one.  I've followed the steps in my rounding algorithm and they appear to be working correctly.  It's gotta be a math thing.  Where are these crazy long values coming from, and how do I get this to work correctly?

Appreciate any help!
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Learn Ruby Fundamentals
LVL 12
Learn Ruby Fundamentals

This course will introduce you to Ruby, as well as teach you about classes, methods, variables, data structures, loops, enumerable methods, and finishing touches.

Nine coins of which three are gold and six are silver in a box. Three coins are selected and placed in bag A. The remaining coins are placed in bag B.
1. Find the probabilities of each possible numbers of gold coins, from 0 to 3, in bag A.

2. on a particular case it is know that one gold coin and two silver cons are in bag A, and that the remaining coins are in bag B. One coin is drawn from a bag selected randomly and put it into another bag. If one coin is then drawn from the last bag, find the probability that it is a gold coin.
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Three ordinary dice are thrown. If the first throw results in just two dice showing the same number, then the die with different number is thrown again. If all numbers are different in the first throw, then all are thrown again. If all numbers are different in the first throw, then all are thrown again. Find the probability that

1. all numbers are the same
2. all numbers are different in a complete turn.

Thx
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I have an index and it is only published quarterly. I want to change it to monthly data.  I did the to the power 1/3 so each month in the quarter has the same return and it produces the same return as the quarter. This causes correlation problems with other indices which has monthly data.

Index 1 (Quarterly Data)
Index 2 (Monthly Data)

Index 1
Quarterly Return 0.48%

Index 2
June -6.71%
July 1.29%
August 2.65%
Which bring this quarterly return to -3.00%.

When I am converting Index 1 to monthly data , i would like to use Index 2 as a guidance.  So, it needs to weighted using the Index 2 data when making Index 1 monthly.

I tried the following.

For June Index 2 x1 = (1+ -6.71%)/(1+ 3%) - 1
For July Index 2 x2 =(1+ 1.29%)/(1+ 3%) - 1
For August Index 3 x3 = (1+ 2.65%)/(1+ 3%) - 1

For June Index 1  y1= (x1/(x1+x2+x3)) * 0.48%        (0.48% is the quarterly return for Index 1)
For July Index 1 y2= (x2/(x1+x2+x3)) * 0.48%        (0.48% is the quarterly return for Index 1)
For August Index 1  y3= (x3/(x1+x2+x3)) * 0.48%        (0.48% is the quarterly return for Index 1)

Then when I compound (1+y1)(1*y2)(1*y3) - 1 = 0.48% So it worked for this quarter.

It works great for some quarters but it doesn't work for some quarters. In some quarters, when I compound y1 y2 y3, i get a number very different from the actual quarterly data for Index 1.  Please see the attached file for the excel file. It has the calculations.
example-data.xlsx
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Attached are few pages from Image Signal Processing textbook.  It talks about how image is acquired from pinhole  Camera model.

They come up with Two equations from matching similar triangles.  Please identify the similar triangles.  And how they come up with Two equations from similar triangles?

My question is in following line of section 1.2.1
"By matching similar triangles we obtain the relations"
 
y = -f * (Y / Z)     and     x = -f * (X / Z)
matching_similar_triangles.docx
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Proper AWG for low voltage application.

I want to run some wire for a low voltage lighting.  The transformer supply will be about 6 -8 feet from the LED lights.  Transformer max output is rated at 36 watts.
36w / 12v = 3Amps.  (max)

Question: What would be safe wire gage to use ?  Was considering using 16AWG lamp cord ?   Most of the documentation and/or charts that I can find online shows 16AWG would be sufficient.  See Attached.
WireSelectionChart.png
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Hi I have a problem, I'm trying to solve for x,
X+1.5x+2x=9π
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Do I need a water-water heat exchanger to run a shower off an Antminer S9-Aqua?

My hovel is currently heated by several crypto-miners but they all blow hot air out and do not provide hot water. If I get a water-cooled mining rig can I connect it directly to my hot water tank or do I need a heat exchanger?

I live in a hard water area. there is a lot of chalk in the tap water which makes it taste nice but tends to clog the pipes.
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Please help me to identify the correct type or find a replacement alternative to the broken mini push button used in GPS Prestigio Geovision 5055 as seen in the photos from attached pdf file.

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How do i get the attached data "normalised" -- made into normal distribution ?

Worksheet "Data" = Full Data
"Filtered 25-65" = data with 25-65 s filtered by "Data" and copied in this worksheet.

If i use 25-65, it has the best result - ie, less skewness but stil not into normal distribution.

Any idea to use that range such that the data plotted is normal distribution  ?
Data-25-65--Check-Normal--EE.xlsx
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Python 3 Fundamentals
LVL 12
Python 3 Fundamentals

This course will teach participants about installing and configuring Python, syntax, importing, statements, types, strings, booleans, files, lists, tuples, comprehensions, functions, and classes.

Hi,

Is there a way to calculate percentile rank using a conditional statement. For example, PERCENTRANK.EXC of column Ratio if Rating value is AAA. Example is attached.

Thanks
EE-example.xlsx
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Hi,

I am unable to understand how we can derive: (S,K and cap are positive integers)

3*( max(S-K,0) – max(S – (K+Cap/3),0))

from

3* min(max((S – K,0), Cap/3)

From plugging values in 3* min(max((S – K,0), Cap/3) , I can see that it is equivalent. But how do i think about this?

Thanks
1
I'm exploring the use of drones to do delivery (for items that weigh up to 20kg
ie about 44 lbs) of dimensions up to 2ft long x 2ft wide x 10 inches thick.  

Once local authority approves it, thought of sourcing/purchasing some of these
drones but will need to look into the cost effectiveness (ie its  gasoline/petrol
costs, maintenance/repair) or is there any that uses rechargeable powerbanks?

Has Amazon or any country done it & what's the safety & regulatory requirements?
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Hi,
I would like to prepare data for regression analysis.
I can prepare data in two forms.
a) values
b) rankings.
example:
values  60,30,25,90
rankings 2,3,4,1
Which format would be most suitable or does it not matter ?
many thanks
Ian
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We need an MBR, but it needs to be returned as a 5 point polygon.

Test sample :

with OrientedPoint as
   (
      SELECT 1 AS OrientedPoint, sdo_geometry(3001,31370,NULL,sdo_elem_info_array(1,1,1,4,1,0),sdo_ordinate_array(1,11,0,1,0,0))  AS geom FROM dual union all
      SELECT 2 AS OrientedPoint, sdo_geometry(3001,31370,NULL,sdo_elem_info_array(1,1,1,4,1,0),sdo_ordinate_array(2,12,0,1,0,0))  AS geom FROM dual union all
      SELECT 3 AS OrientedPoint, sdo_geometry(3001,31370,NULL,sdo_elem_info_array(1,1,1,4,1,0),sdo_ordinate_array(3,13,0,1,0,0))  AS geom FROM dual union all
      SELECT 4 AS OrientedPoint, sdo_geometry(3001,31370,NULL,sdo_elem_info_array(1,1,1,4,1,0),sdo_ordinate_array(4,14,0,1,0,0))  AS geom FROM dual union all
      SELECT 5 AS OrientedPoint, sdo_geometry(3001,31370,NULL,sdo_elem_info_array(1,1,1,4,1,0),sdo_ordinate_array(5,15,0,1,0,0))  AS geom FROM dual union all
      SELECT 6 AS OrientedPoint, sdo_geometry(3001,31370,NULL,sdo_elem_info_array(1,1,1,4,1,0),sdo_ordinate_array(11,21,0,1,0,0)) AS geom FROM dual union all
      SELECT 7 AS OrientedPoint, sdo_geometry(3001,31370,NULL,sdo_elem_info_array(1,1,1,4,1,0),sdo_ordinate_array(11,31,0,1,0,0)) AS geom FROM dual union all
      SELECT 8 AS OrientedPoint, sdo_geometry(3001,31370,NULL,sdo_elem_info_array(1,1,1,4,1,0),sdo_ordinate_array(15,21,0,1,0,0)) AS geom FROM dual union all
      SELECT 9 AS OrientedPoint, …
0
The question is from Physics book titled "Physics for Scientists and Engineers" by Randall D. Knight.  Attached is part of chapter 10.1.

"Objects A and B are oblivious to our choice of system, so change in total kinetic energy for system 2 is exactly the same as for system 1."

How is that possible?  System 1 has kinetic energy because there are external forces but System 2 doesn't have external forces.
interactive_system.PNG
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