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Anybody here good with math and formulas? I have a problem I can't get past.

What is the total resistance of this circuit?

1/R = 1/6.25 + 1/7.5

Also, can you list step by step on how you figured this out?

Thanks a ton :thumbup:
 

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Anybody here good with math and formulas? I have a problem I can't get past.

What is the total resistance of this circuit?

1/R = 1/6.25 + 1/7.5

Also, can you list step by step on how you figured this out?

Thanks a ton :thumbup:
1/R=1/6.25 + 1/7.5

1/R= .16 + .133 = .293

1/R= .293

Multiply both side by R

1= .293 x R

divide both sides by .293

1/.293 = R

3.41= R
 

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Anybody here good with math and formulas? I have a problem I can't get past.

What is the total resistance of this circuit?

1/R = 1/6.25 + 1/7.5

Also, can you list step by step on how you figured this out?

Thanks a ton :thumbup:
If those two resistors are in parrallel
I.E. 6.25 & 7.5
then its 3.44 ohms.

1/6.25 = .16

1/7.5 = .13

.16 + .13 = .29

1/.29 = 3.44
 

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Anybody here good with math and formulas? I have a problem I can't get past.

What is the total resistance of this circuit?

1/R = 1/6.25 + 1/7.5

Also, can you list step by step on how you figured this out?

Thanks a ton :thumbup:
This is for a parallel circuit, A good little "check sum" is that your solution will be less than any of your individual resistances. If you come up with a number larger than any of your original resistance values you have done something wrong.
 

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Anybody here good with math and formulas? I have a problem I can't get past.

What is the total resistance of this circuit?

1/R = 1/6.25 + 1/7.5

Also, can you list step by step on how you figured this out?

Thanks a ton :thumbup:
get rid of denominators.


6.25*1/R = 6.25*1/6.25+ 6.25*1/7.5

6.25/R= 1 + 6.25/7.5

7.5*6.25/R = 7.5 + 7.5*6.25/7.5

7.5*6.25/R = 7.5 + 6.25

7.5*6.25*R/R = (7.5+6.25)*R
7.5*6.25 = 13.75R

7.5*6.25/13.75 = R
 

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get rid of denominators.


6.25*1/R = 6.25*1/6.25+ 6.25*1/7.5

6.25/R= 1 + 6.25/7.5

7.5*6.25/R = 7.5 + 7.5*6.25/7.5

7.5*6.25/R = 7.5 + 6.25

7.5*6.25*R/R = (7.5+6.25)*R
7.5*6.25 = 13.75R

7.5*6.25/13.75 = R
That sure looks like a lot of key strokes to get the answer when all you have to do is add the reciprocals of all of the resistors that are in parallel and then take the reciprocal of the sum.
 
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