mr and mrs smith, their 2 children and fog want to cross a river in a boat that would hold only 80 kg and both mr. amd Mrs Smith have a mass of 80 kg and both the children have a mass of 40 kg and the dog has a mass of 5 kg explain how they can cross the river in the fewest crossings possible
2=160 (parents) or could it be 40 kg each
2= 80 ( kids) or could kids be 20 kg each???
1= 5 kg (dog)
So 1 parent (40kg), 1 kid (20kg), 1dog (15kg) total = 75.
They go across and kid ( 20kg) comes back.
So 1 parent 40kg) and 1 kid (20kg) go across.
Answer 3 trips
Not sure if this is correct.
Let me know
Thanks
Your approach is almost correct, but there is a better way to cross the river in the fewest possible crossings. Here's the step-by-step solution:
1. Mrs. Smith (80 kg) and one child (40 kg) cross the river.
- Total weight: 80 kg + 40 kg = 120 kg
2. Mrs. Smith (80 kg) comes back alone.
- Total weight: 80 kg
3. Mr. Smith (80 kg) and the other child (40 kg) cross the river.
- Total weight: 80 kg + 40 kg = 120 kg
4. One child (40 kg) comes back alone.
- Total weight: 40 kg
5. Mrs. Smith (80 kg) and the dog (5 kg) cross the river.
- Total weight: 80 kg + 5 kg = 85 kg
6. Mrs. Smith (80 kg) comes back alone.
- Total weight: 80 kg
7. Finally, Mr. Smith (80 kg) crosses the river.
- Total weight: 80 kg
By following this sequence, they can cross the river in a total of 7 trips, which is the minimum number of crossings required.
Your answer is almost correct, but there is a more efficient solution that can be done in fewer crossings. Here's the step-by-step explanation:
Step 1: Both children (40kg each) cross the river together. Total weight = 80kg.
Step 2: One child (40kg) returns to the starting side. Total weight = 40kg.
Step 3: One parent (80kg) crosses to the other side. Total weight = 80kg.
Step 4: The other parent (80kg) returns to the starting side. Total weight = 80kg.
Step 5: One child (40kg) crosses to the other side. Total weight = 40kg.
Step 6: The other child (40kg) returns to the starting side. Total weight = 40kg.
Step 7: One child (40kg) crosses to the other side. Total weight = 40kg.
So, in a total of 7 crossings, the entire family and dog can successfully cross the river.