River Crossing with one Torch

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?

River Crossing with one Torch




Similar Riddles

Complete the table series riddle by finding the number that can replace "??".

Tabular Math for All

Asked by Neha on 25 Sep 2024


What four weights can be used to balance from 1 to 30 pounds?

Asked by Neha on 25 Apr 2022

You are playing a game with your friend Jack. There are digits from 1 to 9. You both will take turn erasing one digit and adding it to your score. The first one to score 15 points will win the game.

Would you want to play first or second?

PS: The sum should be exactly 15.

Asked by Neha on 16 Dec 2020


Which letter of the alphabet has the most water?

Asked by Neha on 03 Aug 2025

Next Number in the Series,

5, 16, 49, 104, ?

Asked by Neha on 31 Dec 2025

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?

Asked by Neha on 17 Mar 2025


Find the next number in the series.
1 10 24 43 67 ?

Asked by Neha on 26 Jun 2024

You need to arrange three 7 and mathematical symbols to form number 1?

Asked by Neha on 02 Jul 2021

Find the mistake in the below maths equations

A = 2
A(A-1) = 2(A-1)
A2-A = 2A-2
A2-2A = A-2
A(A-2) = A-2
A = 1

Asked by Neha on 15 Oct 2024


What brings you down but never up?

Asked by Neha on 22 Oct 2021

Hot Articles

Amazing Facts

Gamers

In 2011, people playing Foldit, an online puzzle game about protein folding, resolved the structure of an enzyme that causes an Aids-like disease in monkeys. Researchers had been working on the problem for 13 years. The gamers solved it in three weeks.