3.46 times 10 to the 13th millimeters is how many kilometers? We're not going to convert directly from millimeters into kilometers, we're going to go through the basic unit into meters and then from meters we'll go into kilometers, we don't know the conversion factor from millimeters to kilometers we don't have that memorized. But we do have the conversion from millimeters to meters and then meters to kilometers, so we write what we are given, we always show the units and we always multiply the units we want to factor out which is millimeters will go on the bottom. The units that we factor in meters again that's the basic unit will go on top. A 1 always go in front of the unit with the prefix in this case, mili, and on top in front of meters we're going to put 10 to the minus 3rd. We have that memorized from the conversion chart.

Because we know that there's a ten to the minus 3 meters in one millimeter. Now, we're going to multiply again millimeters cancelled out. We'll put meters on the bottom and the units we want kilometers on top. Again, the 1 goes in front of the prefix and 10 to the 3rd goes in front of meters. When we have an exponent on top we simply multiply or in this case we're going to take the 10 to the 13th and subtract -- we're going to subtract 3 from 13 that gives us 10 to the 10th power and this 3 is on the bottom so that's dividing by 10 to the 3rd so we're going to subtract another 3. And so our answer comes out to be 3.46 times 10 to the 7th kilometers. And that's our final answer.