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I need help solving this task, if anyone had a similar problem it would help me. The task is:

What is the equivalent resistance in a circuit?

I tried the following:
\$Re = \frac{(1000+1000) \times (1000+200)} {(1000+1000) + (1000+200)} = 750\ \Omega\$

enter image description here

Is it exactly 700 or 750 ohms ?

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    \$\begingroup\$ For school questions you have to show your best attempt to solve it so we're not just doing your homework for you. \$\endgroup\$
    – K H
    Commented Jan 20, 2021 at 10:35
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    \$\begingroup\$ I'll give you a hint: You may be overcomplicating it. It's very simple. \$\endgroup\$
    – K H
    Commented Jan 20, 2021 at 10:37
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    \$\begingroup\$ I'm telling you what the rules on stack exchange are to get help. It's really simple. It's killing me that I just can't tell you. All you need to do is use the series and parallel resistance rules to combine the resistors. They've just put in a dead short to mess with you, but the resistance in paralell rule tells you what to do with that. \$\endgroup\$
    – K H
    Commented Jan 20, 2021 at 10:40
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    \$\begingroup\$ Edit your attempt into the question rather than in the comments. \$\endgroup\$
    – Transistor
    Commented Jan 20, 2021 at 10:51
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    \$\begingroup\$ Re=(1000+1000)*(1000+200)/(1000+1000)+(1000+200)=750 ohms ? Explain why you're (trying to) calculate it like that. The calculation doesn't really matter, the method does. Instead of immediately doing calculations, look at the circuit and realize what can be done to simplify it. When I do that the only calculations I have to do is (two 1000 ohms in parallel) 1000 ohms / 2 = 500 ohms and 500 ohms + 200 ohms = 700 ohms \$\endgroup\$
    – Bimpelrekkie
    Commented Jan 20, 2021 at 10:52

1 Answer 1

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The leftmost part is a closed circuit, and that shorts the vertical 1k resistor on the left. You are left with two 1k’s in parallel, so 500 ohm, that goes in series with the 200 ohm resistor, making it 700 ohm.

(answering because you tried in the comments)

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  • \$\begingroup\$ That's what I got too. I'd give you a vote but I've reached my limit for the day. I'll try to remember to give you an upvote tomorrow. Try to get people to edit the question before you answer though because now if OP doesn't edit the question and the comments get deleted, the question will look incomplete. \$\endgroup\$
    – K H
    Commented Jan 20, 2021 at 10:57
  • \$\begingroup\$ Thanks, will do! \$\endgroup\$
    – Sixaxix9
    Commented Jan 20, 2021 at 11:31

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