Sum of Resistance in Parallel Circuits

If two or more resistors are connected in parallel, the overall resistance of the circuit reduces. It is possible to calculate the total resistance of a parallel circuit by using this formula:

Create a function that takes a list of parallel resistance values, and calculates the total resistance of the circuit.

Worked Example

parallel_resistance([6, 3, 6]) ➞ 1.5

# 1/RTotal = 1/6 + 1/3 + 1/6
# 1/RTotal = 2/3
# RTotal = 3/2 = 1.5

Examples

parallel_resistance([6, 3]) ➞ 2

parallel_resistance([10, 20, 10]) ➞ 4

parallel_resistance([500, 500, 500]) ➞ 166.6
# Round to the nearest decimal place

Notes

• Note that you should rearrange to return the RTotal, not 1 / RTotal.
• Round to the nearest decimal place.
• All inputs will be valid.