Metric system pros
1) The metric system is a system of measurements. For example there are fixed formulas between the 7 base units of the metric system.
2) The metric system is a properly maintained system of measurements. Although units have not changed in value, some unit definitions have updated as technology has advanced.
3) There is no duplication of metric units. The meter is always the same length, the kilogram is always the same mass, worldwide. Unlike for example the mile (international mile, US survey mile and nautical mile) or the gallon (US and Imperial).
4) Metric measures are simple to learn. The metric system uses powers of 10 to scale up or scale down. To scale up to larger units we divide by 10 or multiples of 10. To scale down we multiply by 10 or multiples of 10. This is the same as the decimal system which we use for normal numbers and is therefore simple to learn.
5) The metric system is an international language of measures. Over 170 countries and 95% of the worlds population use metric measures as their primary system of measurement.
Metric system con
1) Words like kilometer, kilogram, millimeter, centimeter, ect are too long. Some english speaking countries that use metric measures have abbreviated these words to one syllable words. For example kilometer has become kay or click, and kilogram has become kilo.
I cant think of any other metric cons.
But note ... the following will most likely be mentioned as a metric con, but its not really.
Its said that 12 which is used in Imperial measures,can be divided by 2 3 and 4 and that 10 which is used in metric measures, can be divided by 2 and 5 only.
12 relates to only 2 Imperial units, the foot and the yard.
10 relates to all metric units. But because 10 can only be divided by 2 and 5 this is not a problem for metric measures because for example 1 meter can be described as 100 centimeters or 1000 millimeters. 1 meter is 1000 millimeters and 1000 millimeters can be divided by 2, 4, 5, 8, 10, 20, 25, 40, 50, 100, 125, 200, 250, and 500. A lot more numbers than the foot or yard. Also another metric con will be the fact that 10 cannot be divided by 3. The meter. 1000 millimeters can be divided by 3 but not exactly. For example when using metric measures 1000 millimeters divided by 3 is 333.333 mm its not exact but its OK because we only have to extend the reoccurring 3 to gain more precision. For example 333.33333 mm is more precise (more exact) than 333.333 mm.
Imperial system (Imperial measures) pro
1) All Imperial measures have since 1959 been defined with metric units of measurements. For example The length of 1 yard is exactly 0.9144 meters and therefore the mile is 1609.344 meters.
I cant think of any other Imperial pros.
Imperial system (Imperial measures) con
1) Although the Imperial system maybe called a system its not really. Unlike the metric system there is no formula or connection between for example length and weight.
2) Some Imperial units have more than one value which can cause confusion. For example there are 3 ounces, the fluid ounce, the avoirdupois ounce, and the troy ounce.
3) Imperial measures are more difficult to learn than metric measures because there is no constant value between different units. For example 12 inches in a foot, 3 feet in a yard, 1760 yards in a mile.
4) There is no set symbols for Imperial measures. For example the symbol for mile can be m or mi the symbol for inch can be in or " and the symbol for foot or feet can be ft or ' .
5) Imperial measures cannot be used for international communication because only the US and 2 other countries ( Liberia and Myanmar ) use it as their primary measurements.
I hope this helps answer your question.
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