Minimum Time Bridge Crossing Puzzle

1. It takes 1 min for Jack to cross the bridgee.
2. It takes 2 mins for his sister to cross the bridge.
3. It takes 5 mins for his dad to cross the bridge.
4. It takes 10 mins for his mom to cross the bridge.
5. As the bridge is old only 2 of them can cross it at a time. And while crossing it together, fastest needs to walk together with slow pace, so takes more time.
6. As it is a night, they can't cross the bridge without torch and they have only one torch.

What will be the minimum time required for all of them to cross the bridge?

Scroll down to check your answer.

Answer : 17 minutes

Step 1 : Jack and his sister crosses the bridge and Jack returns back with torch.
Time Taken : 3 mins (2 + 1)
Step 2 : Jacks's Dad and Mom crosses the bridge and Jack's sister returns back with torch.
Time Taken : 12 mins (10 + 2)
Step 3 : Jack and his sister crosses the bridge
Time Taken : 2 mins

Total Time Taken : 17 minutes (3+12+2)