My problem is R1=16 R2=10 R3=? R4=20 Rt=3.582 I3=3.2A

Now I did the 1/R1 + 1/R2 etc

which gets me to .2125, so I did 1/.2125

that leads me to... 4.705882353 for an Rt, that excludes R3's resistance.... I think?

I cant figure out how to use that to calculate my R3...

I also did 1/Rt which equaled .279173, I imagine that might be necessary to find R3?

The answers are in the back of the book so I know what R3 should be, but without knowing how to get there, it does me no good haha.

This is my first post, I did try searching and didn't really find what I was looking for... Thanks for any help on this issue, great site you guys got going here, Im sure Ill be on here quite a bit throughout my apprenticeship. Hopefully I'll be able to contribute to someone else's question one of these days.

Now I did the 1/R1 + 1/R2 etc

which gets me to .2125, so I did 1/.2125

that leads me to... 4.705882353 for an Rt, that excludes R3's resistance.... I think?

I cant figure out how to use that to calculate my R3...

I also did 1/Rt which equaled .279173, I imagine that might be necessary to find R3?

The answers are in the back of the book so I know what R3 should be, but without knowing how to get there, it does me no good haha.

This is my first post, I did try searching and didn't really find what I was looking for... Thanks for any help on this issue, great site you guys got going here, Im sure Ill be on here quite a bit throughout my apprenticeship. Hopefully I'll be able to contribute to someone else's question one of these days.

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