MathsCBSE Class 10 · Basic · Board exam 2026, set 430/4/1 · 1 mark · MCQ

CBSE Class 10 Mathematics Basic 2026: question 5

Set in the CBSE Class 10 board exam of 2026, paper 430/4/1, section A, question 5, for 1 mark. Try it first; the hints and our step-by-step solution are below.

Q5 · 1 mark · MCQReal Numbers

Probability of getting an irrational number at random from the numbers $3, 4, 39, 38, 5, 0, 4^{\frac{3}{2}}$ is :

(A) $0$
(B) $\frac{4}{7}$
(C) $\frac{3}{7}$
(D) $1$

Source: official question paper from cbse.gov.in (PDF). See it in the full 2026 board paper, set 430/4/1.

Hints

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

Hint 1

Simplify each number first.

Hint 2

Count how many of the simplified numbers are not perfect squares or integers.

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.

$4 = 2$ , $39 = 9$ , $0$ and $4^{3/2} = 8$ are rational. $3$ , $38 = 62$ and $5$ are irrational.
There are 3 irrational numbers out of 7, so $P = \frac{3}{7}$ , option (C).
1 mark

Answer: 3/7, option (C)

Where the marks are

Identifies the 3 irrational numbers out of 7 (1 mark)

Revise the chapter

Chapter: Real Numbers (notes, formulas, where marks are lost and every past question)
Topic: Proving Numbers Irrational

Practise this chapterBoard-style questions from Real Numbers, one at a time, marked against the answer key and marking points.Back to the full paper2026 board paper, set 430/4/1 (Basic): 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.

CBSE Class 10 Mathematics Basic 2026: question 5

Hints

Step-by-step solution

Revise the chapter

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