Why did imperial change to metric?

Answer 1

Because metric is far simpler to use.

To use the metric system all you need to know is the 10 times table, or simpler still, know how to move the decimal point. This is because measurement units increase or decrease by factors of 1000, with smaller subdivisions at 10.

You do need to know some prefices, but the same ones are used for mass, length, volume etc. So there are only one set of prefices for a range of measures. Finally, there are simpler and more links across units that measure different attributes.

The Imperial system requires you to learn and remember a whole list of conversion factors for measuring the same attribute (length, mass, volume, etc). And then be familiar with the multiplication tables for at least the following:

2 - for pint to quart

3 - for feet to yard

4 - for quart to gallon

6 - for feet to fathom

8 - for furlongs to mile

12 - for inches to foot

14 - for pounds to stone

16 - for ounces to pound

20 - for fluid ounces to pint

etc