A circuit contains three resistors, two ideal ammeters, and an ideal battery. The readings of the ammeters are 0.40 A and 0.60 A. After two of the resistors are swapped with each other, the reading of each ammeter remains the same. Find the battery current.

We received many solutions to our January Challenge, The January Joints. We are pleased to recognize the following contributors:

Guidelines for contributors:

Many thanks to all contributors and we hope to hear from many more of you in the future!

Note: as always, we would very much appreciate reader-contributed original Challenges.

Boris Korsunsky, Column Editor

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