In geotown, there are 210 teenagers that own a tablet. This is at least 4/5 of all teenagers that live in geotown. What is the maximum number of teenagers who live in geotown?

Let x = the number of teenagers in Geotown.

At least 4/5 of x equals 210. Therefore

(4/5) x ≥ 210

Multiply each side by 5.

4x ≥ 210*5 = 1050

x ≥ 1050/4 = 262.5

Because x ≥ 262.5, therefore x = 263 (x must be an integer).

Answer: 263