Section A – 1 Mark Each (4 × 1 = 4)
Q1. State whether the decimal expansion of
is terminating or non-terminating.
(Similar to CBSE 2019)
Q2. Write the HCF of two consecutive natural numbers.
(Similar to CBSE 2020)
Q3. Is the number 0.3750.375 a rational number? Give reason.
(Similar to CBSE 2022)
Q4. Write the prime factorisation of 90.
(Similar to CBSE 2021)
Section B – 2 Marks Each (4 × 2 = 8)
Q5. Find the LCM of 24 and 36 using prime factorisation method.
(Similar to CBSE 2019)
Q6. Check whether
has a terminating decimal expansion or not.
(Similar to CBSE 2024)
Q7. Find the HCF of 135 and 225 using Euclid’s Division Algorithm.
(Repeated: CBSE 2024)
Q8. Express
in decimal form.
(Similar to CBSE 2023)
Section C – 3 Marks Each (2 × 3 = 6)
Q9. Use Euclid’s Division Algorithm to find the HCF of 867 and 255.
(Repeated: CBSE 2024)
Q10. Find the largest positive integer that divides 398 and 436 leaving remainders 7 and 11 respectively.
(Similar to CBSE 2024)
Section D – 4 Marks (1 × 4 = 4)
Q11. Prove that
is irrational.
(Repeated: CBSE 2024, similar in 2022 & 2020)
Check solution and answer of each question in the video!
Some Additional Practice Questions for Practice
A. 1 Mark Questions
- Write the decimal expansion of

- State whether 0.1010010001… is a rational or irrational number.
- Write the HCF of 1 and any prime number.
- Is the number
a rational number? Give reason.
B. 2 Marks Questions
- Find the LCM of 18 and 30 using prime factorisation.
- Check whether the decimal expansion of
is terminating or non-terminating.
- Express
in decimal form.
C. 3 Marks Questions
- Use Euclid’s Division Algorithm to find the HCF of 455 and 42.
- Find the largest number that divides 615 and 963 leaving remainder 6 in each case.
- Find the HCF and LCM of 24 and 90 and verify that:
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D. 4 Marks Questions
- Prove that
is irrational.
- Prove that
is irrational.









