Circle the shortest time. 70 minutes, 10 minutes, 45 minutes, or one hour.
Which of these four times that we’ve been given is the shortest time? Well, out of 70, 10, 45, and one, the smallest number is one. So should we circle one hour because one is a smaller number than all the other numbers? Well, to compare times, we do need to look at the numbers and we do need to compare them. But we also need to look at the unit of measurement.
Three of the times are shown in minutes. But the last time is shown in hours. So we can’t just compare the numbers. Let’s write the last time in minutes too to help us then compare all the times. One hour is the same as 60 minutes. Now the question becomes a lot easier. We need to find the shortest time out of 70 minutes, 10 minutes, 45 minutes, or 60 minutes. And the smallest of these numbers is the number 10. 10 minutes is the shortest time.
We found the answer by comparing the four different numbers. But before we did this, we had to convert one of the times into minutes. So all of the times we’re using the same unit of measurement. The shortest time is 10 minutes.