# Question Video: Identifying a Suitable Unit to Measure the Width of a Given Object Mathematics • 4th Grade

Choose an appropriate unit for measuring the width of the Atlantic Ocean. [A] centimetres [B] inches [C] feet [D] yards [E] miles

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### Video Transcript

Choose an appropriate unit for measuring the width of the Atlantic Ocean. Centimetres, inches, feet, yards, or miles.

Our five possible answers are all units of measurement that we use to measure length. Because of this, we could actually measure the width of the Atlantic Ocean using any of these units. But they wouldn’t all be appropriate. We’re asked to choose an appropriate unit. What makes a unit appropriate to measure in? Well, there are two things, really.

Firstly, it must be a measurement that isn’t too large. For example, we wouldn’t even measure the length of a boat in centimetres because the number would be so large. The width of the entire ocean would be millions of centimetres. And the second thing that makes a unit appropriate is linked to this. It’s how easy it is to visualise a length.

Just as a quick example, the width of the Atlantic Ocean in centimetres is 880 million centimetres. How can we imagine this? It’s very difficult to visualise because the number is so large. So, an appropriate unit for such a long distance needs to be the longest possible unit we could use. And out of our possible five answers, the longest unit is the mile. The most appropriate unit for measuring the width of the Atlantic Ocean is miles.