This family has 5 members. Each one has a dog. They need to cross a steam so they rented a boat that could only carry 3 living things, dogs or people. Each dog was only comfortable only with its owner and could not be near another person, not even momentarily, unless its owner was present. Dogs could be with other dogs. The crossing would have been impossible except taht Lisa's dog wad attnded a first-rate obediance school and knew how to operate a boat. No other dogs could. How mas the crossings arranged, how many trips did it take?
2007-06-07 15:51:16 · 4 answers · asked by dip_d_chip 1 in Science & Mathematics ➔ Alternative ➔ Other - Alternative
I'll call the other people Person A to Person D with corresponding dogs Dog A to Dog D.
Trip 1: Person A takes Dog A across and returns.
Trip 2: Lisa's dog takes Dog B and Dog C across and returns.
Trip 3: Person A takes Person B and Person C across and comes back with Dog A.
Trip 4: Lisa and her dog cross. Person C and Dog C come back.
Trip 5: Person A, Person B and Person C cross. Lisa's dog comes back.
Trip 6: Lisa's dog takes Dog A and Dog B across and returns.
Trip 7: Lisa's dog takes Dog C across.
2007-06-07 17:02:37 · answer #1 · answered by Scarlet Manuka 7 · 1⤊ 2⤋
this or similar is in most puzzle books. Just look for a river crossing puzzle and you can copy it
2007-06-08 01:25:07 · answer #2 · answered by Father Ted 5 · 0⤊ 1⤋
dogs can swim
2007-06-08 16:32:43 · answer #3 · answered by henry d 5 · 1⤊ 0⤋
logic answer,:who cares?
2007-06-07 23:06:21 · answer #4 · answered by kokopelli 6 · 1⤊ 2⤋