Carol has two kinds of hourglass timers: one which runs for exactly 7 minutes, and the other which runs for exactly 11 minutes:How can Carol measure a time of exactly 15 minutes using these timers? Remember that an hourglass won’t give you a second-by-second countdown.
Answers
Step-by-step explanation:
Take the 11-minute hourglass and 7-minute hourglass and start their time. When the 7-minute hourglass runs out put it aside. You will have 4 minutes left in the 11-minute hourglass. That starts your 15 minutes. Let the 4 minutes run out and then turn the 11–minute hourglass over and after it empties 15 minutes will have run by.
Made my calculations based on assumption that the hourglasses are encased.
P.S. If the question allows for this you could just count to 60 slow so that a minute goes by then let the 7 minute hourglass run through twice. That's how I would do it.
P.S. P.S. Read the comment by Erik Haga. I was about to correct my answer and realized his comment gave the perfect way. please please please please please please please please mark me as brainlist and thank me.mememememem
Answer:
Take the 11-minute hourglass and 7-minute hourglass and start their time. When the 7-minute hourglass runs out put it aside. You will have 4 minutes left in the 11-minute hourglass. That starts your 15 minutes. Let the 4 minutes run out and then turn the 11–minute hourglass over and after it empties 15 minutes will have run by.