For example, you might first try and count the how many numbers
less than 124 are divisible just by 3. Or by 2 and 3. Then you
can throw in the 5's once you see what is going on.
As always, be sure to explain the
work you did to arrive
at your answers!
This is a counting problem, similar to but not exactly like
the last one. One feature in common with yesterday is that you need
to count the elements of a rather complicated set. And it might be
a good idea to consider a simplified version of the problem first.