Metric system is pretty strait forward. here’s a pretty basic demo, elementary school grade explanation ( and the ones we most use daily ) this is for distances.
Let’s take 1 meter as basic measurement .
1 m = 3,28084 foot, feet ? nevermind…
How much is a meter ?
easy just add 3.386 inches ( whatever that is) to a yard and you have 1 meter
mm - cm - dm - m - Dam - Hm - Km
So.
1m ( meter ) has 10 dm ( decimetres)
1 m ( meter) has 100 cm ( centimetres )
1m has 1000 mm ( millimetres )
1 Dam ( decametre ) = 10 metres
1 Hm ( Hectometre ) = 100 metres
1 KM ( kilometre ) = 1000 metres
same goes for weight measurements, liquids and so on .
Basically you only have to multiply or divide by ten each time you move sideways or up and down.