Question

Why is the metric system of measurement convenient to use?

Answer 1

Because it's so much simpler and easier to use. The metric system is an improvement over the English system in three major areas:
1. There is only one unit of measurement for each physical quantity.
2. You can use multiplying prefixes to express the size of a measurement by using a multiplying prefix. For example, 1 000 m = 1 km; 0.001 m = 1 mm.
3. It is a decimal system. Fractions are expressed as decimals. This allows unit conversions without doing math — simply by shifting the decimal point.
You can find a much more comprehensive argument at
http://www.metric4us.com/why.html