If Rosa’s age is represented by R, which inequality represents the
statement “Rosa is at most 29 years old”?
(1) R < 29 (3) R ≤ 29
(2) R > 29 (4) R ≥ 29
The answer is (3) R ≤ 29. At most 29 years old means that the highest age is 29. And she may be 29 years old. So the "equal" need to exist. Then the answer is R≤29.