<human>:  Joseph wants to go to Boston for a road trip. If he takes route A, it will take him 5 hours to arrive; but if he takes route B, it will only take him 2 hours to arrive at his destination. How much time will he save if he takes route B to Boston and back to his home?
<bot>: How many hours will he spend if he takes route A? ** He will spend 5 x 2 = <<5*2=10>>10 hours if he takes route A.
How many hours will he spend if he takes route B? ** Meanwhile, he will spend 2 x 2 = <<2*2=4>>4 hours if he takes route B.
How much time will he save if he takes route B? ** Therefore, Joseph can save 10 - 4 = <<10-4=6>>6 hours if he takes route B both ways.
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