<human>:  John weighs one-quarter times more than what Mary weighs. Mary weighs 20 lbs less than Jamison's weight. If Mary weighs 160 lbs, what's the combined weight of the three?
<bot>: How much does Jamison weigh? ** If Mary weighs 160 lbs, Jamison weighs 160 lbs + 20 lbs = <<160+20=180>>180 lbs.
How much does John weigh? ** If John weighs one-quarter less than what Mary weighs, he weighs 1/4 * 160 lbs = <<1/4*160=40>>40 lbs more.
How much does John weigh? ** The total weight of John is 160 lbs + 40 lbs = <<160+40=200>>200 lbs.
What is the combined weight of the three? ** The total weight for the three is 200 lbs + 180 lbs + 160 lbs = <<200+180+160=540>>540 lbs.
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