CBSE Class 8 Mathematics Rational Numbers MCQ Assignment Set 01

Question. Is \(\frac{1}{0}\) a rational number ?
(a) yes
(b) No
(c) Undefined
Answer: (b) No

Question. \(-\left|\frac{3}{4} - \frac{2}{3}\right|\) is equal to
(a) \(-\frac{1}{12}\)
(b) \(\frac{1}{12}\)
(c) \(\frac{5}{12}\)
Answer: (a) \(-\frac{1}{12}\)

Question. The additive inverse of \(-\frac{c}{d}\) is
(a) \(\frac{c}{d}\)
(b) \(\frac{d}{c}\)
(c) \(-\frac{d}{c}\)
Answer: (a) \(\frac{c}{d}\)

Question. \(-\frac{3}{4} - \left(-\frac{5}{6}\right)\) is
(a) \(-\frac{1}{12}\)
(b) \(\frac{1}{12}\)
(c) \(\frac{5}{12}\)
Answer: (b) \(\frac{1}{12}\)

Question. The sum of two rational numbers is \(-10\) and one of them is \(-4\frac{1}{2}\). The other number is
(a) \(\frac{11}{2}\)
(b) \(\frac{9}{2}\)
(c) \(-\frac{11}{2}\)
Answer: (c) \(-\frac{11}{2}\)

Question. The reciprocal of \(-\frac{7}{12}\) is
(a) \(\frac{7}{12}\)
(b) \(\frac{12}{-7}\)
(c) \(\frac{-12}{-7}\)
Answer: (b) \(\frac{12}{-7}\)

Question. The multiplication of \(\frac{12}{7}\) by \(0\) gives us
(a) \(0\)
(b) \(\frac{12}{7}\)
(c) \(-\frac{12}{7}\)
Answer: (a) \(0\)

Question. By what rational number should \(-\frac{7}{48}\) be multiplied to get \(49\)
(a) \(-\frac{48}{7}\)
(b) \(-49\)
(c) \(-336\)
Answer: (c) \(-336\)

Question. How many rational numbers can come between \(2\) and \(4\)
(a) \(1\)
(b) \(2\)
(c) Infinite
Answer: (c) Infinite

Question. A rational number between \(\frac{1}{2}\) and \(\frac{1}{3}\) is
(a) \(\frac{5}{12}\)
(b) \(\frac{5}{6}\)
(c) does not lie
Answer: (a) \(\frac{5}{12}\)

Question. Which is a true statement
(a) \(\frac{5}{12} > \frac{3}{7}\)
(b) \(\frac{5}{12} < \frac{3}{7}\)
(c) \(\frac{5}{12} = \frac{3}{7}\)
Answer: (b) \(\frac{5}{12} < \frac{3}{7}\)

Question. If \(\frac{1}{8}\) , \(\frac{1}{2}\) , \(\frac{1}{4}\) are arranged in ascending order then the middle number is
(a) \(\frac{1}{4}\)
(b) \(\frac{1}{2}\)
(c) \(\frac{1}{8}\)
Answer: (a) \(\frac{1}{4}\)

Question. The difference between greatest and least of \(-\frac{5}{9}\) , \(\frac{2}{9}\) , \(-\frac{4}{9}\) is
(a) \(-\frac{1}{3}\)
(b) \(-\frac{2}{9}\)
(c) \(\frac{7}{9}\)
Answer: (c) \(\frac{7}{9}\)

Question. If \(\frac{5}{6} + \frac{3}{2} = \frac{3}{2} + \frac{5}{6}\) , the property used is
(a) closure
(b) Commutative
(c) Associative
Answer: (b) Commutative

Question. If \(\frac{3}{4} > \frac{2}{5}\) then \(-\frac{3}{4} > -\frac{2}{5}\) is
(a) True
(b) False
(c) neither of these
Answer: (b) False

Question. \( -\frac{2}{3} \times \frac{3}{5} + \frac{5}{2} - \frac{3}{5} \times \frac{1}{6} \)
Answer: 2

Question. \( \frac{2}{5} \times \left( -\frac{3}{7} \right) - \frac{1}{6} \times \frac{3}{2} + \frac{1}{14} \times \frac{2}{5} \)
Answer: \( -\frac{11}{28} \)

Question. \( \frac{5}{7} + \frac{1}{3} + \frac{8}{9} + \frac{1}{14} \)
Answer: \( \frac{253}{126} \)

Subtract the first rational number from the second in each of the following:

Question. \( \frac{3}{8}, \frac{5}{8} \)
Answer: \( \frac{1}{4} \)

Question. \( -\frac{7}{9}, \frac{4}{9} \)
Answer: \( \frac{11}{9} \)

Question. \( \frac{9}{11}, -\frac{2}{11} \)
Answer: \( -\frac{7}{11} \)

Question. \( \frac{4}{13}, -\frac{11}{13} \)
Answer: \( -\frac{15}{13} \)

Question. \( \frac{3}{8}, -\frac{1}{4} \)
Answer: \( -\frac{5}{8} \)

Question. \( \frac{5}{6}, -\frac{2}{3} \)
Answer: \( \frac{3}{2} \)

Question. \( \frac{13}{14}, -\frac{6}{7} \)
Answer: \( -\frac{1}{14} \)

Question. \( \frac{7}{22}, -\frac{8}{33} \)
Answer: \( -\frac{5}{66} \)

Question. The sum of the two numbers is \( \frac{5}{9} \). If one of the numbers is \( \frac{1}{3} \), find the other.
Answer: \( \frac{2}{9} \)

Question. The sum of two numbers is \( -\frac{1}{3} \). If one of the numbers is \( -\frac{12}{3} \), find the other.
Answer: \( \frac{11}{3} \)

Question. The sum of two numbers is \( -\frac{4}{3} \). If one of the numbers is –5, find the other.
Answer: \( \frac{11}{3} \)

Question. The sum of two rational numbers is –8. If one of the numbers is \( -\frac{15}{7} \), find the other.
Answer: \( -\frac{41}{7} \)

Question. What should be added to \( -\frac{7}{8} \) so as to get \( \frac{5}{9} \)?
Answer: \( \frac{103}{72} \)

Question. What number should be added to \( -\frac{5}{11} \) so as to get \( \frac{26}{33} \)?
Answer: \( \frac{41}{32} \)

Question. What number should be added to \( -\frac{5}{7} \) to get \( -\frac{2}{3} \)?
Answer: \( \frac{1}{21} \)

Question. What number should be subtracted from \( -\frac{5}{3} \) to get \( \frac{5}{6} \)?
Answer: \( -\frac{5}{2} \)

Question. What number should be subtracted from \( \frac{3}{7} \) to get \( \frac{5}{4} \)?
Answer: \( -\frac{23}{28} \)

Question. What should be added to \( \left( \frac{2}{3} + \frac{3}{5} \right) \) to get \( -\frac{2}{15} \)?
Answer: \( -\frac{7}{5} \)

Question. What should be added to \( \left( \frac{1}{2} + \frac{1}{3} + \frac{1}{5} \right) \) to get 3?
Answer: \( \frac{59}{30} \)

Question. What should be subtracted from \( \left( \frac{3}{4} - \frac{2}{3} \right) \) to get \( -\frac{1}{6} \)?
Answer: \( \frac{1}{4} \)

Simply each of the following and write as a rational number of the form \( \frac{p}{q} \):

Question. \( \frac{3}{4} + \frac{5}{6} + \left( -\frac{7}{8} \right) \)
Answer: \( \frac{17}{24} \)

Question. \( \frac{2}{3} + \left( -\frac{5}{6} \right) + \frac{-7}{9} \)
Answer: \( -\frac{17}{18} \)

Question. \( \frac{-11}{2} + \frac{7}{6} + \frac{-5}{8} \)
Answer: \( -\frac{119}{24} \)

Question. \( \frac{-4}{5} + \frac{-7}{10} + \frac{-8}{15} \)
Answer: \( -\frac{61}{30} \)

Question. \( \frac{-9}{10} + \frac{22}{15} + \frac{13}{-20} \)
Answer: \( -\frac{1}{12} \)

Question. \( \frac{5}{3} + \frac{3}{-2} + \frac{-7}{3} + 3 \)
Answer: \( \frac{5}{6} \)

Express each of the following as a rational number of the form \( \frac{p}{q} \):

Question. \( \frac{-8}{3} + \frac{-1}{4} + \frac{-11}{6} + \frac{3}{8} - 3 \)
Answer: \( -\frac{175}{24} \)

Question. \( \frac{6}{7} + 1 + \frac{-7}{9} + \frac{19}{21} + \frac{-12}{7} \)
Answer: \( \frac{80}{63} \)

Question. \( \frac{15}{2} + \frac{9}{8} + \frac{-11}{3} + 6 + \frac{-7}{6} \)
Answer: \( \frac{263}{24} \)

Question. \( \frac{-7}{4} + 0 + \frac{-9}{5} + \frac{19}{10} + \frac{11}{14} \)
Answer: \( \frac{15}{140} = \frac{3}{28} \)

Question. \( \frac{-7}{4} + \frac{5}{3} + \frac{-1}{2} + \frac{-5}{6} + 2 \)
Answer: \( \frac{7}{12} \)

Simplify:

Question. \( \frac{-3}{2} + \frac{5}{4} - \frac{7}{4} \)
Answer: –2

Question. \( \frac{5}{3} - \frac{7}{6} + \frac{-2}{3} \)
Answer: \( -\frac{1}{6} \)

Question. \( \frac{5}{4} - \frac{7}{6} - \frac{-2}{3} \)
Answer: \( \frac{3}{4} \)

Question. \( \frac{-2}{5} - \frac{-3}{10} - \frac{-4}{7} \)
Answer: \( \frac{33}{70} \)

Question. \( \frac{5}{6} + \frac{-2}{5} - \frac{-2}{15} \)
Answer: \( \frac{17}{30} \)

Question. \( \frac{3}{8} - \frac{-2}{9} + \frac{-5}{36} \)
Answer: \( \frac{33}{72} = \frac{11}{24} \)