Units and the decimal point

Express two point three five kilometres in metres. Here is the length of the path: two point three five kilometres. The path stays exactly as long as it is. We are only changing the unit we count it in. How many metres? There are one thousand metres in one kilometre. Here is one kilometre of the path. The same piece is one thousand metres. The next whole kilometre also contains one thousand metres. And part of the next kilometre completes the path. The whole path is two point three five lots of one thousand metres. Two point three five times one thousand. Two thousand, three hundred and fifty metres. The length has not changed. A metre is smaller than a kilometre, so it takes more of them. The number is bigger.

Your turn. Express one hundred and eighty four centimetres in metres. Here is a strip, one hundred and eighty four centimetres long. How many metres is that? Try it first. Pause if you like. We keep the same strip and change the unit. There are one hundred centimetres in one metre. Lay one metre along the strip. This same part is one hundred centimetres. What is left is less than another metre. A metre is bigger than a centimetre, so it takes fewer of them. The number will be smaller. One hundred and eighty four divided by one hundred. One point eight four metres. One hundred and eighty four in centimetres. One point eight four in metres. The strip is the same strip. Only the unit is different. A smaller unit means more units. A larger unit means fewer units.