In solving this problem, you should know the basic place
values:
For example:
243. in this example, 200 is the hundreds, 40 is the tens and
the 3 is the ones.
So for our problem, 235 if rounded off to the nearest tens,
it would be 240. Since according to the rules if the ones is 5 and above, the
number will be rounded off.
We round down if the ones is 4 and below.
