L
Leese
Guest
A family 5 got lost in the jungle during a picnic by the river and it was nearly dark. Don't ask me why, but they just got lost while exploring the jungle and got up to a creek or something and came to an old bridge.
They are:
1. the old grandfather who walks with a stick,
2. a stocky, slightly overweight father
3. a mother
4. an elder brother in his 20s
5. a younger brother in his teens who happens to be an athlete
As the darkness fell, the father remember he packed a lamp in his backpack and took it out as they need help with lighting to cross the bridge.
Once the lamp was lit - to their dismay there's a sign that says only two adults can cross the bridge at the same time as the bridge cannot hold more than 2 adults on it at any one time.
And the lamp could only last 30 seconds before it is extinguished and they will be in total darkness.
Now, quick - think of a strategy to enable them to cross over - two by two - but the lamp needs to be carried back by ONE person over to the other side so that those waiting on the other side may cross. The speed for each member of the family to cross the same distance are:
1. Grandpa - 12 seconds (one way)
2. Father - 8 seconds (one way)
3. Mother - 6 seconds (one way)
4. Older Brother - 3 seconds (one way)
5. Younger Brother - 1 second (one way)
The speed of the pair follows the speed of the slower person, example, if you get the father and mother to cross together, the time taken is 8 seconds and NOT 6 seconds as the mother has to wait for the father as they're sharing one lamp.
How can they do it? =S
They are:
1. the old grandfather who walks with a stick,
2. a stocky, slightly overweight father
3. a mother
4. an elder brother in his 20s
5. a younger brother in his teens who happens to be an athlete
As the darkness fell, the father remember he packed a lamp in his backpack and took it out as they need help with lighting to cross the bridge.
Once the lamp was lit - to their dismay there's a sign that says only two adults can cross the bridge at the same time as the bridge cannot hold more than 2 adults on it at any one time.
And the lamp could only last 30 seconds before it is extinguished and they will be in total darkness.
Now, quick - think of a strategy to enable them to cross over - two by two - but the lamp needs to be carried back by ONE person over to the other side so that those waiting on the other side may cross. The speed for each member of the family to cross the same distance are:
1. Grandpa - 12 seconds (one way)
2. Father - 8 seconds (one way)
3. Mother - 6 seconds (one way)
4. Older Brother - 3 seconds (one way)
5. Younger Brother - 1 second (one way)
The speed of the pair follows the speed of the slower person, example, if you get the father and mother to cross together, the time taken is 8 seconds and NOT 6 seconds as the mother has to wait for the father as they're sharing one lamp.
How can they do it? =S