Welcome to Brainly! I'm happy to help!
We see that there are 1,610 meters in a mile. However, we are looking for millimeters, not meters. But, knowing the meters will help us out.
A millimeter is a very small measurement. There are 1,000 millimeters in 1 meter. A meter is much larger. So, if we want to convert 1,610 meters to millimeters, there are going to be way more millimeters because they are so minute.
This means that we will have to multiply. We know that there are 1,000 millimeters in 1 meter, so if we multiply our meters by 1,000 (which is basically just adding 3 zeros), we will get the number of millimeters in one mile!
1,610×1,000=1,610,000 (one million six hundred and ten thousand!)
Don't forget that we are looking for 3 miles though, so we can take the number of millimeters in one mile and multiply by three.
1,610,000×3=4,830,000 (four million eight hundred and thirty thousand!)
So, Tobias ran 4,830,000 millimeters!
Have a wonderful day and keep on learning! :D
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