Class 8 Maths Worksheet: Rational Numbers

📘 Class 8 Maths Worksheet

Topic: Rational Numbers

Name: ____________ Class: 8 Date: ____________


✏️ Section A: Basic Level (Concepts & Identification)

  1. Define a rational number.
  2. Which of the following are rational numbers?
    a) 35\frac{3}{5}53​
    b) 2\sqrt{2}2​
    c) -7
    d) 0.25
  3. Write two rational numbers between 0 and 1.
  4. Write the additive inverse of 56\frac{5}{6}65​.
  5. Write the multiplicative inverse of 34-\frac{3}{4}−43​.
  6. Is 0 a rational number? Give reason.
  7. Convert 72\frac{7}{2}27​ into decimal form.

✏️ Section B: Medium Level (Operations)

  1. Simplify: 23+16\frac{2}{3} + \frac{1}{6}32​+61​
  2. Simplify: 5814\frac{5}{8} – \frac{1}{4}85​−41​
  3. Multiply: 35×109\frac{3}{5} \times \frac{10}{9}53​×910​
  4. Divide: 78÷1416\frac{7}{8} \div \frac{14}{16}87​÷1614​
  5. Simplify: 23+56-\frac{2}{3} + \frac{5}{6}−32​+65​
  6. Arrange in ascending order: 12,23,34\frac{1}{2}, \frac{2}{3}, \frac{3}{4}21​,32​,43​

✏️ Section C: Advanced Level (Word Problems)

  1. A rope of length 56\frac{5}{6}65​ m is cut into 2 equal parts. What is the length of each part?
  2. A student scored 35\frac{3}{5}53​ of total marks in Maths and 45\frac{4}{5}54​ in Science. Find total fraction score.
  3. If x=23x = \frac{2}{3}x=32​, find 3x+123x + \frac{1}{2}3x+21​.
  4. The sum of two rational numbers is 74\frac{7}{4}47​. One number is 34\frac{3}{4}43​. Find the other.
  5. A tank is 35\frac{3}{5}53​ filled. If 25\frac{2}{5}52​ is added, what fraction is filled now?

✏️ Section D: Higher Order Thinking (HOTS)

  1. If a=23a = \frac{2}{3}a=32​, find a+1aa + \frac{1}{a}a+a1​.
  2. Prove that sum of two rational numbers is always rational (example based).
  3. Find a rational number between 25\frac{2}{5}52​ and 35\frac{3}{5}53​.
  4. If x+1x=3x + \frac{1}{x} = 3x+x1​=3, find possible value of xxx (rational).
  5. Write 3 rational numbers between 1-1−1 and 000.

  1. Without dividing, compare: 79\frac{7}{9}97​ and 56\frac{5}{6}65​.

✅ Answer Key

✏️ Section A: Basic Level

  1. A rational number is a number that can be written in the form pq\frac{p}{q}qp​, where q0q \ne 0q=0.
  2. Rational numbers: a, c, d
    ( 35\frac{3}{5}53​, -7, 0.25 )
  3. Any two examples: 13,23\frac{1}{3}, \frac{2}{3}31​,32​ (or similar)
  4. −56-\frac{5}{6}−65​
  5. −43-\frac{4}{3}−34​
  6. Yes, because 0 = 01\frac{0}{1}10​
  7. 3.5

✏️ Section B: Medium Level

  1. 23+16=56\frac{2}{3} + \frac{1}{6} = \frac{5}{6}32​+61​=65​
  2. 5814=38\frac{5}{8} – \frac{1}{4} = \frac{3}{8}85​−41​=83​
  3. 35×109=23\frac{3}{5} \times \frac{10}{9} = \frac{2}{3}53​×910​=32​
  4. 78÷1416=1\frac{7}{8} \div \frac{14}{16} = 187​÷1614​=1
  5. 23+56=16-\frac{2}{3} + \frac{5}{6} = \frac{1}{6}−32​+65​=61​
  6. Ascending order:
    12,23,34\frac{1}{2}, \frac{2}{3}, \frac{3}{4}21​,32​,43​

✏️ Section C: Advanced Level

  1. Each part = 512\frac{5}{12}125​ m
  2. Total = 75\frac{7}{5}57​
  3. x=23x = \frac{2}{3}x=32​:
    3x+12=2+12=523x + \frac{1}{2} = 2 + \frac{1}{2} = \frac{5}{2}3x+21​=2+21​=25​
  4. Other number = 111
  5. Filled fraction = 1 (fully filled tank)

✏️ Section D: HOTS

  1. a=23a = \frac{2}{3}a=32​:
    a+1a=23+32=136a + \frac{1}{a} = \frac{2}{3} + \frac{3}{2} = \frac{13}{6}a+a1​=32​+23​=613​
  2. Example proof:
    Let ab+cd=ad+bcbd\frac{a}{b} + \frac{c}{d} = \frac{ad + bc}{bd}ba​+dc​=bdad+bc​, which is rational.
  3. One example: 12\frac{1}{2}21​ (or any valid number between)
  4. Possible values: x=3±52x = \frac{3 \pm \sqrt{5}}{2}x=23±5​​
    (Note: may not always be rational; depends on interpretation)
  5. Any three rational numbers between -1 and 0:
    −14,−12,−34-\frac{1}{4}, -\frac{1}{2}, -\frac{3}{4}−41​,−21​,−43​

  1. Compare 79\frac{7}{9}97​ and 56\frac{5}{6}65​:
    Cross multiply:
    7×6=427 \times 6 = 427×6=42, 5×9=455 \times 9 = 455×9=45
    👉 56\frac{5}{6}65​ is greater