Class 8 Rational Numbers CBSE Questions & Answers

Class 8 · Rational Numbers

This is Mathematics Class 8 Rational Numbers CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
Find the reciprocal of -2.
  • A
    \(\frac{{ - 1}}{2}\)
    Correct
  • B
    2
  • C
    -2
  • D
    none of these
2
Write the rational number that is equal to its negative.
  • A
    -1
  • B
    2
  • C
    1
    Correct
  • D
    0
3
Write the additive inverse of \(\frac{2}{3}\).
  • A
    \( - \frac{2}{3}\)
    Correct
  • B
    \(\frac{2}{3}\)
  • C
    1
  • D
    0
4
Find the multiplicative inverse of -13.
  • A
    -13
  • B
    12
  • C
    \(\frac{{ - 1}}{{13}}\)
    Correct
  • D
    13
5
Name the property under multiplication used in \(\frac{{ - 1}}{5} \times ( - 5) = - 5 \times \frac{{ - 1}}{5} = 1\).
  • A
    Commutative property
  • B
    Reciprocal
    Correct
  • C
    Associative property
  • D
    none of thes Multiplicative identity e
6
A number which can be written in the form\(\frac{p}{q}\) , where p and q are integers and \(q \ne {\text{ }}0\) is called a _________.
  • A
    negative number
  • B
    irrational number
  • C
    none of these
  • D
    rational number
    Correct
7
Sum of two rational numbers is a _______.
  • A
    negative number
  • B
    rational number
    Correct
  • C
    none of these
  • D
    irrational number
8
For any three rational numbers a, b and c, a + (b + c) = __________.
  • A
    (a + b) - c
  • B
    (a - b) - c
  • C
    (a - b) + c
  • D
    (a + b) + c
    Correct
9
\(\_\_\_\_\_\_\_ = {\text{ 1 }} \times a = a\) for any rational number a.
  • A
    \(a \times {\text{ }}0\)
  • B
    \(a \times {\text{ 1}}\)
    Correct
  • C
    \(a \times {\text{ 2}}\)
  • D
    \(a \times {\text{ 3}}\)
10
Find \(\frac{3}{7} + \left( { - \frac{6}{{11}}} \right) + \left( { - \frac{8}{{21}}} \right) + \frac{5}{{22}}\)
  • A
    \(\frac{{ - 125}}{{462}}\)
    Correct
  • B
    -125
  • C
    125
  • D
    462
11
Find the reciprocal of \(\frac{{ - 1}}{5}\).
  • A
    -5
    Correct
  • B
    \(\frac{{ - 1}}{5}\)
  • C
    none of these
  • D
    5
12
\(\frac{1}{4}{\text{ }} \times {\text{ 1 }} = {\text{ }}\_\_\_\_\)
  • A
    \(\frac{1}{4}\)
    Correct
  • B
    1
  • C
    0
  • D
    4
13
Write the additive inverse of \(\frac{4}{5}\).
  • A
    \(\frac{4}{5}\)
  • B
    \( - \frac{4}{5}\)
    Correct
  • C
    1
  • D
    0
14
Find the multiplicative inverse of\(\frac{1}{4}\).
  • A
    -4
  • B
    4
    Correct
  • C
    \(\frac{1}{4}\)
  • D
    \( - \frac{1}{4}\)
15
Name the property under multiplication used in\(\frac{{ - 1}}{5} \times 1 = 1 \times \frac{{ - 1}}{5} = \frac{{ - 1}}{5}\).
  • A
    none of these
  • B
    Multiplicative identity
    Correct
  • C
    Commutative property
  • D
    Associative property