You turn the 7 minute one and the 11 minutes one at the same time. When the 7 one finishes, turn it again. When the 11 one finishes, you know that 4 minutes have passed, with 4 minutes to get to the desired 15, all you need to do now is turn the 7 minute hourglass again since it counted 4 minutes, and when it runs out it'll be exactly 15 minutes.
Start both hourglasses then when the 11 minute hourglass has finished immediately flip it again. When the 13 minute hourglass runs out the 11 minute hourglass will have 9 minutes left, so flip it and it will last another 2 minutes, 13 minutes + 2 minutes = 15 minutes.
Four people need to cross a bridge in 17 minutes in the middle of the night. The bridge can only hold two or less people at any time and they only have one flashlight so they must travel together (or alone). The flashlight can only travel with a person so every time it crosses the bridge it must be carried back. Tom can cross in 1 minute, John can cross in 2 minutes, Sally can cross in 5 minutes, and Connor can cross in 10 minutes. If two people cross together they go as fast as the slower person.How can they cross the bridge in 17 minutes or less?
First Tom and John will cross (2 minutes). Then Tom will bring the flashlight back (1 minute). Next Sally and Connor will cross (10 minutes). Then John will bring the flashlight back (2 minutes). Finally John and Tom will cross (2 minutes). 2 + 1 + 10 + 2 + 2 = 17 minutes.
You have a 4 minute sand clock and a 7 minute sand clock, you need to measure 9 minutes while using both of them. What's your first move?
(The 'Google Riddles' are interview questions those who wish to get hired were asked).
I can flutter and take your breath away. I can take a beating, but do not bruise. If I stopped you would be sure to lose. Everyday I am with you. What am I?
Trains travel from one town to another town all day, always on the same track, always going nonstop and at the same speed. The noon train took 80 minutes to complete the trip, but the 4 PM train took an hour and 20 minutes. Why?
Subscribe and REMOVE ALL ADS
LOVE our articles but HATE our ads? For only $3.89 per month, enjoy a seamless, ad-free experience that lets you focus on what matters most — enjoying all of our content, uninterrupted. 🔒 100% Secure Payment 📅 Cancel Anytime, No Strings Attached Unlock a cleaner, faster browsing experience today and gain the freedom to navigate without visual clutter.
Ready for a Ad-Free experience? Upgrade now for just $3.89/month!
To enable your Ad-Free Subscription, please fill the fields below
Thank you for your subscription!
Your subscription was successful, now you can enjoy an ad-free experience!! Note: To make sure you get no ads, please make sure to log in to your account. If you are logged in already, then refresh the page. The subscription can be cancelled at any time.
Go to BabaMail
