Help reading simple equation

Klang

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Sep 18, 2020
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Well this is embarrassing but I'm struggling with reading the bellow equation.

So t' is adjusted time with new filtration and t = current exposure time
The dots signify multiplication and the line is division but in what order would the sum be done as I cannot seem to get any where near the answer in the example?

Meopta.JPG

Thank you
 

Subhotosh Khan

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You said, "I cannot seem to get any where near the answer..."
What answer/s did you get?

Please show your work in getting those answer/s.​
 

Klang

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Sep 18, 2020
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What answer/s did you get?

Please show your work in getting those answer/s.​
Hi,

Well if I take the top row for example and multiply them i.e. 1.17x2.01x1.00 and then do the same for the bottom 1.14 etc, then divide the totals of each. But that doesn't take into account the time etc

Or is it t i.e. 10 x 1.17 divided by 1.14
 

Subhotosh Khan

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Hi,

Well if I take the top row for example and multiply them i.e. 1.17x2.01x1.00 and then do the same for the bottom 1.14 etc, then divide the totals of each. But that doesn't take into account the time etc

Or is it t i.e. 10 x 1.17 divided by 1.14
Please rewrite the complete equation with which you are working and then show your work.
 

firemath

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Oct 29, 2019
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Well this is embarrassing......
Don't be embarrassed. That will not help you win the struggle. Everyone needs help sometimes.

:)
 

HallsofIvy

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Hi,

Well if I take the top row for example and multiply them i.e. 1.17x2.01x1.00 and then do the same for the bottom 1.14 etc, then divide the totals of each. But that doesn't take into account the time etc

Or is it t i.e. 10 x 1.17 divided by 1.14
Yes, of course- your equation clearly says t times the fraction \(\displaystyle \frac{km'\cdot ky'\cdot kc'}{km\cdot ky \cdot kc}\) and each example, with t= 10, shows 10 times the fraction.
 

Klang

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Yes, of course- your equation clearly says t times the fraction \(\displaystyle \frac{km'\cdot ky'\cdot kc'}{km\cdot ky \cdot kc}\) and each example, with t= 10, shows 10 times the fraction.
Thank you got it.

10x(1.17x2.01x1.00)÷(1.14x1.69x1.00)=12.20 Seconds

I guess to expand on that so the above gives me the correct answer when inputted into a scientific calculator but out of interest in what order would this equation be performed when using a non scientific calculator i.e. written by hand or with a calculator without the brackets function. Does that question make sense?
 

Subhotosh Khan

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Thank you got it.

10x(1.17x2.01x1.00)÷(1.14x1.69x1.00)=12.20 Seconds

I guess to expand on that so the above gives me the correct answer when inputted into a scientific calculator but out of interest in what order would this equation be performed when using a non scientific calculator i.e. written by hand or with a calculator without the brackets function. Does that question make sense?
You may do it as follows:

1.17*2.01 = 2.3517

2.2517*1 = 2.3517

2.3517 / 1.14 = 2.0628947368421

2.06289 / 1.69 = 1.2206449704142

and so on....
 

HallsofIvy

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Thank you got it.

10x(1.17x2.01x1.00)÷(1.14x1.69x1.00)=12.20 Seconds

I guess to expand on that so the above gives me the correct answer when inputted into a scientific calculator but out of interest in what order would this equation be performed when using a non scientific calculator i.e. written by hand or with a calculator without the brackets function. Does that question make sense?
Since only multiplication and division are involved, the order doesn't matter!a

If there were multiplications mixed with additions, then using "Please Excuse My Dear Aunt Sally" or "PEMDAS", 'parentheses", "exponents", "multiplication", "division", "addition", "subtraction", you would do all multiplications before the additions.
 

Subhotosh Khan

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Since only multiplication and division are involved, the order doesn't matter!a

If there were multiplications mixed with additions, then using "Please Excuse My Dear Aunt Sally" or "PEMDAS", 'parentheses", "exponents", "multiplication", "division", "addition", "subtraction", you would do all multiplications before the additions.
Just be careful with those divisions - without parentheses.
 
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