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).

263

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.

The answer is 9.7 cm