Bridge Crossing in Minimal Time

A family is trapped in a jungle. There is a bridge which can lead them to safety. But at one time, the bridge can only allow two people to pass through. Also, all of them are afraid of the dark and thus, they can't go alone.

Father takes 1 minute to cross, the mother takes 2 minutes, the son takes 4 and the daughter takes 5 minutes. While crossing the time taken will be according to the slower one. How can they all reach the other side in the minimum possible time?




Similar Riddles

Can you count the number of quadrilaterals in the picture below?

Count the Quadrilaterals

Asked by Neha on 14 Mar 2023


Known by all without exception, Forever here, for your protection, Sometimes strong, sometimes weak, Right after the night I come - hot and chic. And while millions of miles away, I always get to you, I find my way. No life around could do without me, Can you guess what I might be?

Asked by Neha on 05 Apr 2022

A rain drop fell from one leaf to another leaf and lost 1/4th of its volume. It then fell to another leaf and lost 1/5th of the volume. It again fell on another leaf and lost 1/5th of the volume.



This process kept repeating till it fell on the last leaf losing 1/75th of its volume.



Can you calculate the total percentage of loss from the initial volume when the drop has fallen to the last leaf accurate up to two decimal places?

Asked by Neha on 16 Feb 2021


I am a type of food that is often found in the fridge and can be white in colour. What I am?
Hint 1: I am a dairy product.
Hint 2: You can spread me on the bread.

Asked by Neha on 30 Sep 2025

Can you find out the remainder when 3^300 is divided by 5?

Asked by Neha on 31 Oct 2023

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Asked by Neha on 02 Nov 2024


How can a man go eight days without sleep?

Asked by Neha on 11 Mar 2024

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

Asked by Neha on 07 Feb 2025

There are 3 apples in the basket and you take away 2. How many apples do you have now?

Asked by Neha on 21 Oct 2025


Four people need to cross a rickety bridge at night. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. The bridge is only strong enough to support two people at a time. Not all people take the same time to cross the bridge. Times for each person: 1 min, 2 mins, 7 mins and 10 mins. What is the shortest time needed for all four of them to cross the bridge?

Asked by Neha on 24 Aug 2023

Hot Articles

Amazing Facts

Gambling

In Canada, a mathematical puzzle must be solved in order to win the lottery to classify it as a “game of skill” not gambling.