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Incorrect: 0
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Edexcel GCSE Maths (Non-calculator) Smart practice A mixed round aimed at your weak spots
Unit 1
Number
Unit 2
Algebra
Unit 3
Ratio, proportion and rates of change
Unit 4
Geometry and measures
Unit 5
Probability
Unit 6
Statistics
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Inequalities

Practise 36 exam-style questions on Inequalities for Edexcel GCSE Maths (Non-calculator). Write your answer as you would in the exam and get it marked in seconds against the mark scheme, point by point, with an AI tutor on hand if you get stuck.

  • 36 questions
  • 1–5 marks each
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20 questions, marked as you go

Sample questions with model answers

Here are 4 of the questions in this topic, each with a model answer, an explanation of why it earns the marks and the mark scheme an examiner would use.

Question 1

2 marks

Solve \(5 - 2x \le 11\)

Model answer

\(5 - 2x \le 11\)
\(5 - 11 \le 2x\)
\(-6 \le 2x\)
\(-3 \le x\)
So \(x \ge -3\)

Explanation

Adding \(2x\) to both sides keeps the \(x\) term positive and avoids dividing by a negative number. If you divide both sides by \(-2\) instead, you must reverse the inequality sign: \(-2x \le 6\) gives \(x \ge -3\).

Mark scheme
  1. 1 mark

    M1 for \(-2x \le 6\) or \(5 - 11 \le 2x\)

    oe; correct answer with no working scores full marks

  2. 1 mark

    A1 for \(x \ge -3\)

    oe, e.g. \(-3 \le x\); do not accept \(x \le -3\)

Question 2

2 marks

Ben is solving the inequality \(6 - 3x < 12\)
Here is his working.
\(-3x < 6\)
\(x < -2\)

Ben's answer is wrong. Explain his mistake and give the correct answer.

Model answer

Ben divided both sides by \(-3\) without reversing the inequality sign.
\(-3x < 6\)
\(x > -2\)

Explanation

Multiplying or dividing an inequality by a negative number reverses its direction. Check with a value: \(x = 0\) gives \(6 < 12\), which is true, and 0 satisfies \(x > -2\) but not Ben's \(x < -2\).

Mark scheme
  1. 1 mark

    C1 for explaining that when you divide by a negative number (\(-3\)) the inequality sign must be reversed

    oe

  2. 1 mark

    B1 for \(x > -2\)

    oe

Question 3

3 marks

Solve \(x(x - 4) \le 12\)

Model answer

\(x^2 - 4x \le 12\)
\(x^2 - 4x - 12 \le 0\)
\((x - 6)(x + 2) \le 0\)
Critical values: \(x = 6\) and \(x = -2\)
\(-2 \le x \le 6\)

Explanation

Rearrange so that one side is 0 before factorising; you cannot use \(x \le 12\) or \(x - 4 \le 12\). The quadratic is negative or zero between its roots, and both critical values are included because of ≤.

Mark scheme
  1. 1 mark

    M1 for rearranging to \(x^2 - 4x - 12 \le 0\)

    correct answer with no working scores full marks

  2. 1 mark

    M1 for factorising, \((x - 6)(x + 2)\), giving critical values 6 and \(-2\)

  3. 1 mark

    A1 for \(-2 \le x \le 6\)

    oe

Question 4

4 marks

The region R is defined by the inequalities
\(x \ge 0\qquad y \ge x\qquad x + y \le 6\)

Work out the area of R.

Model answer

The boundaries are \(x = 0\) (the \(y\)-axis), \(y = x\) and \(x + y = 6\).
\(y = x\) and \(x + y = 6\) meet where \(2x = 6\), at \((3, 3)\).
\(y = x\) meets \(x = 0\) at \((0, 0)\); \(x + y = 6\) meets \(x = 0\) at \((0, 6)\).
R is the triangle with vertices \((0, 0)\), \((0, 6)\) and \((3, 3)\).
Base along the \(y\)-axis \(= 6\), perpendicular height \(= 3\)
Area \(= \dfrac{1}{2} \times 6 \times 3 = 9\)

Explanation

Find the corners of the region by solving pairs of boundary equations simultaneously. A quick sketch shows that R is a triangle with one side on the \(y\)-axis, so use that side as the base and the horizontal distance to \((3, 3)\) as the height.

Mark scheme
  1. 1 mark

    P1 for identifying the boundary lines \(x = 0\), \(y = x\) and \(x + y = 6\), and that R is a triangle

    correct answer with no working scores full marks

  2. 1 mark

    P1 for finding the vertex where \(y = x\) meets \(x + y = 6\), \((3, 3)\)

  3. 1 mark

    P1 for the other vertices \((0, 0)\) and \((0, 6)\) and a correct method for the area, e.g. \(\dfrac{1}{2} \times 6 \times 3\)

  4. 1 mark

    A1 for 9 (square units)

    cao

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