Ow do you round by tens

Let me explain it using this example.

For example, pretend you have the number 47. When rounding up to the nearest tenth, ask yourself, "What ten number mark is the number closest to?" In this case the number 47 is closer to 50. If the number was, for example 42, then the nearest tenth would be 40. However, if the number is halfway between both tenths, (for example 45) then you always round up to the tenth that is higher. In this case the number is 45, so you would round up to 50.

If it is 5 and below its the lower number ending with zero and if it is 6 and above round up to the nearest zero above the current number