PSAT Math Multiple-Choice Question 837: Answer and Explanation

Question: 837

The final velocity of a given object is given by the following formula:

Final velocity =
Initial velocity + Acceleration × Time

If a ball has an initial velocity of and a constant acceleration of which inequality shows the range of times, T, that will cause the final velocity to have a value of at least

• A. T ≥ 3 seconds
• B. T ≥ 8 seconds
• C. 3 seconds ≤ T ≤ 5 seconds
• D. 6 seconds ≤ T ≤ 22 seconds

Correct Answer: A

Explanation:

(A) Plug the given values into the equation:

The final velocity must be at least . Set up the inequality so that the result for the final velocity could exceed :

22 ≤ 4 + 6T
18 ≤ 6T
3 ≤ T