Skip to content

Tara scored 40 marks in a… (Class 10 Maths 2024, Q32b)

questionbuddy.in/q/cbse-10-maths-2024-30-2-1-q32b-tara-scored-test-getting-right

MathsCBSE Class 10 · Standard · Board exam 2024, set 30/2/1 · 5 marks · Long answer

CBSE Class 10 Mathematics Standard 2024: question 32(b)

Set in the CBSE Class 10 board exam of 2024, paper 30/2/1, section D, question 32(b), for 5 marks. Try it first; the hints and our step-by-step solution are below.

Q32(b) · 5 marks · Long answerPair of Linear Equations in Two Variables

Tara scored marks in a test, getting marks for each right answer and losing mark for each wrong answer. Had marks been awarded for each correct answer and marks been deducted for each wrong answer, then Tara would have scored marks. Assuming that Tara attempted all questions, find the total number of questions in the test.

Source: official question paper from cbse.gov.in (PDF). See it in the full 2024 board paper, set 30/2/1.

Hints

Open one hint at a time and try again before the next.

Hint 1

Use two variables: number of right answers and number of wrong answers.

Hint 2

Write one equation for each marking scheme and solve them by elimination.

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

  1. Let the number of right answers be and wrong answers be . First scheme: …(1)

    1½ marks

  2. Second scheme: , i.e. …(2)

    1½ marks

  3. Subtracting (2) from (1): . From (1): .

    1 mark

  4. Since all questions were attempted, total number of questions .

    1 mark

Answer: 20 questions

Where the marks are

  • Equation (1½ marks)
  • Equation (1½ marks)
  • Solves , (1 mark)
  • Total questions = 20 (1 mark)

Revise the chapter

Practise this chapterBoard-style questions from Pair of Linear Equations in Two Variables, one at a time, marked against the answer key and marking points.Back to the full paper2024 board paper, set 30/2/1 (Standard): every question, by section.

The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.