21/80 = 26.25%
A value like 21/80, or 26.25%, can show up in everyday life when about one-fourth of a group or amount is involved. For example, 21 out of 80 students might ride the bus, or a store might sell about 26% of its stock during a sale.
To picture 21/80 quickly, think of it as a little more than one-fourth. Since one-fourth is 25%, 26.25% is just 1.25 percentage points higher, so a visual model would have slightly more than 25 of every 100 spaces shaded.
A common mistake is to round 26.25% to 26% or 25% and then treat the rounded number as exact. Rounding can be useful for a quick estimate, but the original value is slightly greater than one-fourth.
