math challenge

Weeks of October 20 - November 1, 1997

Hey, I'm on time!

Billy and Sally arrange to meet for a picnic lunch at 12:30 PM. At 8:00 AM, they synchronize their watches and leave for work.

The doomed couple don't know that Billy's watch runs at a rate of five minutes for every six actual minutes, and Sally's watch runs at a rate of six minutes for every five actual minutes.

Both Sally and Billy think they arrive on time (according to their watches), but they actually arrive several minutes apart. How many minutes apart do they arrive for the picnic?

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