The rule

R + W > N. Any read quorum must overlap any write quorum. Read sees at least one replica with the latest write.

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The rule

R + W > N. Any read quorum must overlap any write quorum. Read sees at least one replica with the latest write.

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W=3 R=3 N=5

Both quorums = 3. Overlap of 1 replica guaranteed. Read sees latest write. Strong consistency.