Rewrite the length as an improper fraction.
21 7/8 = 175/8
Write the quantity of stamps as a fraction: 25/1
Divide length by number of stamps:
175/8 / 25/1
When dividing by a fraction change the sign to multiplication and flip the second fraction over:
175/8 x 1/25.
Now multiply numerators and then denominators:
(175 x1) / (8x 25) = 175/200
Simplify to 7/8
Each stamp is 7/8 inches long
