What is mean when it says Reducing a fraction to its simplest terms?
If the numrator and the denominator (the top and the bottom
numbers respectively) of a fraction have a factor in common then
the fraction can be reduced by dividing both the numerator and
denominator by that factor.
For example, 18/24 is not in its simplest form because 2 is a
common factor of 18 and 24.
Dividing both 18 and 24 by 2 gives the reduced form: 9/12.
But this is NOT the end of the story because 9 and 12 also have
a factor in common, which is 3.
Dividing both by 3 gives 3/4.
This IS the end because 3 and 4 have no factor in common (they
are coprime). So the original fraction is now in its reduced
form.
Instead of going though this process step by step, you could
find the greatest common factor of the numerator and denominator
and divide both by the gcf. That would be quicker if you are happy
calculating gcfs.