12/15 = 80%
A value like 12/15, or 80%, can show up when 12 students out of 15 turn in an assignment on time. It could also describe having 12 successful shots out of 15 attempts or finishing 12 of 15 tasks on a checklist.
You can picture 12/15 as four out of every five equal parts, since 80% is close to a large majority. A quick estimate is that it is noticeably more than half but not quite all the way to three-fourths? Actually, 80% is a little more than three-fourths and about one-fifth short of the whole.
A common mistake is treating 12/15 as 12%, even though the denominator shows that the whole group has 15 parts. Another point of confusion is assuming 80% means perfect performance; it still leaves 20% unfinished or incorrect.
