Are you a logical person? Could you use your logic like a tool to solve problems? Then this is where you'll find some great challenges to test your logical skills.
Here you'll find our logic riddles, including short logic riddles, easy logic riddles, hard logic riddles and long logic riddles. All the riddles are with answers.
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.