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The base for a circular pool 2018-06-10
Adam pose la question :
How many sheet of 4ft by 8ft foam would I need to lay under a pool 15dt in diameter
Penny Nom lui répond.
A tangent to a circle 2018-06-10
Bellle pose la question :
Determine the equation of the circle which has its center at (3,1) and tangent 3x-4y+5=0
Penny Nom lui répond.
The inverse square law 2018-06-05
Amy pose la question :

Question about inverse square law ;

Hi, I'm trying to understand some nuances about this law and
have been reading about it a lot online and trying out some homework
for personal interest (hobby ) - not school related.

I understand that the simple formula is ; 1/d^2

I was wondering about what appears to be an oddity to me, that
I came across when I was working with a test example I found at this
link ;

http://www.softschools.com/formulas/physics/inverse_square_law_formula/82/

The problem that caught my interest was this one on that page ;

"1) If a bright flashlight has a light intensity of 15.0 candela at a distance 1.00 m from the lens, what is the intensity of the flashlight 100.0 m from the lens?"

So I have a few different questions about this, but the most important
one is, what does it mean if we replace the "1" in ; 1/d^2 with a different value such as a ratio in the form of a decimal value, so instead we have something like this ;

0.75/d^2

???

Does this ratio represent a curve then?

I am thinking that the "1" in the normal formula represents a straight line

Some of the links I was researching ;

http://wisptools.net/book.php?c=3&s=2

http://www.softschools.com/formulas/physics/inverse_square_law_formula/82/

https://www.nde-ed.org/GeneralResources/Formula/RTFormula/InverseSquare/InverseSquareLaw.htm


Penny Nom lui répond.
Are those two equations the same? 2018-06-05
Francisco pose la question :
Solve for y: 2(x+3)=y x=5
Solve for y: (x+3)2=y x=5
Are those two equations the same?

Penny Nom lui répond.
The difference between two numbers is -3 2018-06-05
Hannah pose la question :
write a pair if integers whose difference is -3 ( given that the greater number is 8 )
Penny Nom lui répond.
The volume of a berm 2018-06-04
Mike pose la question :
Have a berm that is 700’ long, 29’ y’all and needs a 20’ top with 5-1 slope on one side and 3-1 slope in the other
Penny Nom lui répond.
Two odd integers 2018-06-04
Pleroma pose la question :
The product of two alternate odd integers exceeds three times the smaller number by 12. What is the larger number?
Penny Nom lui répond.
$96 is 66 2/3% of what dollar amount? 2018-05-31
mary pose la question :
$96 is 66 2/3% of what dollar amount?
Penny Nom lui répond.
Taking 6 pills 2018-05-29
Dave pose la question :
My motives are simple, I want to get revenge on my brother who, unbeknown to me, repeatedly cheated when we played on-line Scrabble! Can you help? - he has posed this question knowing that I'll struggle to get the solution. Question: He is taking 6 pills a day, if he takes the pills in a different order each day, how long will it be before he takes the pills in the same order on the same date again? I think leap years might come in to it! Will I confess to using you guys? - I'll think about that one.
Penny Nom lui répond.
Monthly Pension 2018-05-28
Kenneth pose la question :

Hello:

I have a question regarding how the units cancel in the following:

A company uses the following calculation to determine the monthly payment for its employees as they retire:

1.1% * average 5 years highest salary * years of service

If an employee worked 33 years and his average 5 year salary is $30,705.17, what is his monthly payment?

I used the following to determine his monthly payment, but I am not sure how the units cancel especially the years.

1.1% * $30,705.17 * 33 years divided by 12 months/year

I determined his payment as $928.83 per month, but the year units do not cancel unless the 1.1% is per year.

Is the correct calculation 1.1%/year * $30,705.17 * 33 years divided by 12 months/year so that the units cancel properly?

The $\$30,705.17$ is an average for 5 years of working. It is not $30,705.17 per year.

I thank you for your assistance.


Penny Nom lui répond.
What is the diameter of the observable universe? 2018-05-27
peter pose la question :
The diameter of the observable universe is calculated to be 92 billion light years. What would that distance be in miles given a light year is 6 trillion miles?
Penny Nom lui répond.
An equation with rational coefficients 2018-05-26
Anagh pose la question :
If x and y are rational number and
(x+y) + (x - 2y)√2 = 2x -y + (x-y-1) √5

Then find the value of x and y.

Penny Nom lui répond.
Converting inches to centimeters 2018-05-25
Jason pose la question :
Hi!
Is there a method to approximately convert inches to cm in my head without using a calculator?

Thanks! Jason

Penny Nom lui répond.
Pre tax and post tax percentages 2018-05-22
Tom pose la question :
Hi,
I work in a clothes shop which can also do mail-orders. My Head Office has sent a report with which we can check the records we keep in store tally with those at HO.

According to that report we have taken £2578.25 in orders, excluding VAT (20%), which would therefore be £3093.91 including VAT (2578.25+20%=3093.91).

According to my records, we have taken £3179.32 including VAT, which would be £2543.45 excluding VAT (3179.32-20%=2543.45).

Why is it that the difference between the VAT inclusive figures (3179.32-3093.91) is +£85.41, but the difference between the VAT exclusive figures (2543.45-2578.26) is -£34.81?

Now, I can see from the report that 1 order has not been recorded by HO, and I know that our average order value is around £30, so the -£34.81 makes sense. But surely both figures should be a minus, regardless of whether they include VAT?

I'm sure there is an obvious answer, but I just cannot see it! Any help would be gratefully received.
Thanks,
Tom

Penny Nom lui répond.
The area, radius and slant height of a cone 2018-05-18
joette pose la question :
If you have a cone how to find the slant height when given the area and radius?
Penny Nom lui répond.
 
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