51/100 = 51%
A value of 51% might show up in a poll where just over half of the people chose one option. It could also describe a battery charge, a sale, or how much of a project is finished.
To picture 51%, imagine 100 small squares with 51 shaded in. It is just a little more than half, so you can estimate it as roughly 50% at a glance.
A common point of confusion is thinking 51% means exactly half. It is one percentage point above 50%, so it represents a little more than half—not a lot more.