Counting by \(10\)s means going up by 10 each term instead of by \(1\).

Here is usual counting: \[1,2,3,4,\dots\]

Here is counting by \(10\)s: \[10,20,30,40,\dots\]

In regular counting by \(1\)s you can start from any number. Here is counting by \(1\)s starting from \(58.\) \[58,59,60,61,62,63,\dots\]

Here is counting by \(10\)s starting from \(68.\) Each term goes up by \(10.\) \[68,78,88,98,108,118,\dots\] Notice that every terms ends in the same number. It is like counting by \(1\)s in the tens place.