Unit Tests: Rational Numbers | Mathematics (Maths) Class 8 PDF Download

Time: 1 hour  

M.M. 30  

Attempt all questions.  

Question numbers 1 to 5 carry 1 mark each.  

Question numbers 6 to 8 carry 2 marks each.  

Question numbers 9 to 11 carry 3 marks each.  

Question numbers 12 & 13 carry 5 marks each

Q1: The product of $\frac{2}{3}$ and $\frac{3}{4}$ is a rational number. (True/False) (1 Mark)

Q2: Write in standard form (lowest terms, positive denominator): (1 Mark)

Q3: What is the multiplicative inverse of $-\frac{7}{9}$? (1 Mark)

Q4: Rational numbers are not closed under which operation? (1 Mark)
(i) Addition
(ii) Subtraction
(iii) Multiplication
(iv) Division

Q5: What is the additive identity of rational numbers? (1 Mark)

Q6: A wire of length $\frac{7}{4}$ meters is cut into two pieces. If one piece is $\frac{5}{8}$ meters long, how long is the other piece? (2 Marks)

Q7: Verify if the rational numbers - 3/4  and -8/5 are closed under multiplication. (2 Marks)

Q8: How does the associative property apply to the addition of rational numbers? (2 Marks)

Q9: (i) Simplify the expression $\frac{3}{5}+\frac{4}{7}$ and express it as a single rational number. (3 Marks)

(ii)  Match the following properties with their descriptions: 

Q10: If $a=\frac{3}{8}$ and $b=\frac{2}{5}$, solve the expression $4a-3b+\frac{a}{b}$. (3 Marks)

Q11: (i) Find any three rational numbers between $\frac{1}{3}$ and $\frac{1}{2}$. Show your working. (3 Marks)

(ii) Prove that the sum of two rational numbers is always a rational number.

Q12: If $x=\frac{3}{4}$ and $y=\frac{2}{3}$, solve the following expression: $x+4y-2xy$. Show all steps. (5 Marks)

Q13:

You can find the solutions of this Unit Test here: Unit Tests(Solution): Rational Numbers