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We are going to calculate the equivalent resistance in parallel circuits.

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In parallel circuits, you don't add the two resistors.

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When you have two resistors that are in parallel, this is the formula to calculate the equivalent resistance.

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For example, here we have two resistors in parallel of 200 ohms and 300 ohms and the battery of 15 volts.

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They ask you to calculate the equivalent resistance first.

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Substitute this 200 and 300 into the formula.

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1 divided by the equivalent resistance is equal to this.

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Make this operation in the calculator.

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Never use common multiples.

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multiples 1 divided by 200 plus 1 divided by 300 it gives you this then

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you have this value 1 divided by equivalent resistance and I need the

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equivalent resistance so you look for this button in your calculator or this

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one and you make the inverse of this figure or make this operation 1 divided

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by the result you have obtained and then it gives you the total equivalent

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resistance that in this case is 120 ohms. Look at the result and check that the

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result is smaller than both of them. And finally to calculate the intensity go to

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the Ohm's law. Intensity is voltage divided by resistance. Voltage of the cell

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divided by the equivalent resistance and then make this operation and you have the total intensity