Important MCQs from Class 9 Maths Chapter 1.3-Real Numbers and their Decimal Expansion
| In this article, you’ll find a set of important and exam-focused MCQs from Class 9 Maths Chapter 1.3-Real Numbers and their Decimal Expansion. These MCQs help you prepare smartly for your upcoming Maths tests. These MCQs are created based on the latest NCERT curriculum. These questions are perfect for students of CBSE, ICSE, IGCSE, NCERT, and various State Boards. See More Chapter MCQs Important MCQs from Class 9 Maths Chapter 1.1 “Number Systems” |
1. The decimal expansion of a rational number is always:
(A) Terminating only
(B) Non-terminating only
(C) Either terminating or non-terminating repeating
(D) Non-terminating non-repeating
Answer: (C) Either terminating or non-terminating repeatingView Answer...
Explanation: A rational number can either have a terminating decimal or a repeating (recurring) decimal.
2. Which of the following numbers has a terminating decimal expansion?
(A) \( \frac{13}{20}\)
(B) \( \frac{7}{12}\)
(C) \( \frac{4}{33}\)
(D) \( \frac{3}{11}\)
Answer: (A) \( \frac{13}{20}\)View Answer...
Explanation: A fraction has a terminating decimal expansion only if the denominator (after simplifying) has prime factors 2 and/or 5 only.
, so it’s terminating.
3. A number with a decimal expansion that terminates is always:
(A) Irrational
(B) Rational
(C) Integer
(D) Natural number
Answer: (B) RationalView Answer...
Explanation: Any number with a terminating decimal can be expressed in the form, so it is rational.
4. If the denominator of a rational number (in lowest form) has prime factors other than 2 or 5, then the decimal expansion is:
(A) Terminating
(B) Terminating with rounding
(C) Non-terminating repeating
(D) Non-terminating non-repeating
Answer: (C) Non-terminating repeatingView Answer...
Explanation: Only denominators with prime factors 2 and/or 5 produce terminating decimals.
5. The number\( 0.454545\ldots\) represents the fraction:
(A) 45/99
(B) 45/100
(C) 5/11
(D) 45/90
Answer: (A) 45/99View Answer...
6. If a rational number \( p/q \) has a terminating decimal expansion, the prime factorization of \( q \) must be of the form:
(A) \( 2^m \times 3^n \)
(B) \( 2^m \times 5^n \)
(C) \( 3^m \times 5^n \)
(D) \( 2^m \times 7^n \)
Answer: (B) \( 2^m \times 5^n \)View Answer...
Explanation: For a rational number \( p/q \) (where \( q \neq 0 )\) to have a terminating decimal expansion, the denominator \( q \), in its simplest form, must have only the prime factors 2 and/or 5, i.e., \( q = 2^m \times 5^n \), where \( m \) and \( n \) are non-negative integers.
7. Which of the following decimal expansions is of a rational number?
(A) 0.1234567891011…
(B) 0.123123123…
(C) 0.1010010001…
(D) None of the above
Answer: (B) 0.123123123…View Answer...
Explanation: This expansion repeats “123” and is non-terminating, recurring, so it represents a rational number
8. The decimal expansion of \( \frac{1}{7}\)is:
(A) Terminating
(B) Non-terminating recurring
(C) Non-terminating non-recurring
(D) Cannot be determined
Answer: (B) Explanation: Since 7 is not a factor of 2 and/or 5, the decimal expansion will be non-terminating.View Answer...
9: Convert\(0.4\bar{7}\)into the form :
(A)
(B)
(C)
(D)
Answer: (C)View Answer...
10. How many digits are in the repeating block of the decimal expansion of ?
(A) 1
(B) 2
(C) 3
(D) 4
Answer: (B) Explanation: . The repeating block is “09”, which has 2 digits.View Answer...