This answer key for the inequalities test gives a worked solution and a scoring guide for each of the 9 questions. Award partial credit as described, and total the score out of 20 points.
Question 1: Writing with Symbols (2 points)
- \(x < 8\)
- \(y \ge 15\)
Scoring: 1 point for each correct inequality.
Question 2: Testing Solutions (2 points)
- \(5 > 5\) is false. Not a solution
- \(7.5 \le 7.5\) is true. A solution
Scoring: 1 point for each correct decision with a valid reason.
Question 3: Listing Solutions (2 points)
Any three numbers that are at least \(10\) work, for example 10, 12, and 25.5. Any number below \(10\) is not a solution, for example 9.9, because \(9.9 \ge 10\) is false.
Scoring: 1 point for three valid solutions (10 counts); 1 point for a valid non-solution.
Question 4: Graphing an Inequality (2 points)
Open circle at \(4\), because \(4 < 4\) is false, and shading to the left.
Scoring: 1 point for an open circle at 4; 1 point for shading to the left.
Question 5: Reading a Graph (2 points)
The closed circle at \(2\) means \(2\) is included, and the shading goes right: \(x \ge 2\).
Scoring: 1 point for the correct symbol; 1 point for the correct number.
Question 6: Greater Than or Equal To (3 points)
- \(3 > 3\) is false. No
- \(3 \ge 3\) is true. Yes
- The graph of \(x > 3\) has an open circle at \(3\); the graph of \(x \ge 3\) has a closed circle at \(3\). Both are shaded to the right.
Scoring: 1 point for each part.
Question 7: Elevator Limit (3 points)
- \(p \le 12\)
- \(12 \le 12\) is true. Yes
- People are counted in whole numbers, so half a person makes no sense. \(p\) must be a whole number.
Scoring: 1 point for each part.
Question 8: Bake Sale Goal (2 points)
- \(d \ge 150\)
- \(150 \ge 150\) is true, so $150 meets the goal. \(149.99 \ge 150\) is false, so $149.99 does not.
Scoring: 1 point for the inequality; 1 point for both decisions.
Question 9: Game Rating (2 points)
Older than \(9\) does not include \(9\): \(a > 9\). Open circle at \(9\) with shading to the right.
Scoring: 1 point for the inequality; 1 point for the correct graph.
20 points
See every chapter on the Grade 6 math page.

