Recurring Decimals / āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āĻĻāĻļāĻŽāĻŋāĻ•


Recurring Decimals / āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āĻĻāĻļāĻŽāĻŋāĻ•


Definition / āĻĒā§°āĻŋāĻ­āĻžāώāĻž


A recurring decimal is a decimal number in which one or more digits repeat forever after the decimal point. āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āĻĻāĻļāĻŽāĻŋāĻ• āĻš’āϞ āĻāύ⧇ āϏāĻ‚āĻ–ā§āϝāĻž āϝ’āϤ āĻĻāĻļāĻŽāĻŋāϕ⧰ āĻĒāĻžāĻ›āϤ āĻāϟāĻž āĻŦāĻž āĻāĻ•āĻžāϧāĻŋāĻ• āϏāĻ‚āĻ–ā§āϝāĻž āĻ…āύāĻ¨ā§āϤāĻ•āĻžāϞāϞ⧈ āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤāĻŋ āĻšāϝāĻŧāĨ¤


Major Points // āĻŽā§āĻ–ā§āϝ āĻŦāĻŋāώ⧟āϏāĻŽā§‚āĻš



  1. A recurring decimal repeats a fixed pattern infinitely. āĻāϟāĻž āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āĻĻāĻļāĻŽāĻŋāĻ• āĻ…āύāĻ¨ā§āϤāĻ•āĻžāϞāϞ⧈ āĻāϟāĻž āύāĻŋā§°ā§āĻĻāĻŋāĻˇā§āϟ āϧ⧰āĻŖ āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤāĻŋ āϕ⧰⧇āĨ¤

  2. It is non-terminating but repeating. āχ āĻļ⧇āώ āύāĻšā§Ÿ āĻ•āĻŋāĻ¨ā§āϤ⧁ āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤāĻŋāĻļā§€āϞāĨ¤

  3. Every recurring decimal can be written as a fraction (rational number). āĻĒā§ā§°āϤāĻŋāĻŸā§‹ āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āĻĻāĻļāĻŽāĻŋāĻ• āĻ­āĻ—ā§āύāĻžāĻ‚āĻļ (rational number) ā§°ā§‚āĻĒ⧇ āϞāĻŋāĻ–āĻŋāĻŦ āĻĒāĻžā§°āĻŋāĨ¤

  4. The repeating part is shown with a bar (  Ė…  ) above digits. āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āĻ…āĻ‚āĻļāĻŸā§‹ āϏāĻ‚āĻ–ā§āϝāĻžā§° āĻ“āĻĒā§°āϤ āĻĻāĻžāĻ— (  Ė…  ) āĻĻāĻŋ āĻĻ⧇āϖ⧁āĻ“ā§ąāĻž āĻšā§ŸāĨ¤


Examples of Recurring Decimals / āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āĻĻāĻļāĻŽāĻŋāϕ⧰ āωāĻĻāĻžāĻšā§°āĻŖ



  • 0.(3) :Decimal Pattern: 3 repeats

  • 0.(12): Decimal Pattern: 12 repeats

  • 5.(42): Decimal Pattern: 42 repeats


Types of Decimals / āĻĻāĻļāĻŽāĻŋāϕ⧰ āĻĒā§ā§°āĻ•āĻžā§°āϏāĻŽā§‚āĻš


Terminating Decimal (Ends) / āĻļ⧇āώ āĻšā§‹ā§ąāĻž āĻĻāĻļāĻŽāĻŋāĻ• āĨ¤ Ex: 0.25, 0.75, 2.4


Non-terminating Decimal (Does not end) / āĻļ⧇āώ āύāĻšā§‹ā§ąāĻž āĻĻāĻļāĻŽāĻŋāĻ•



  • Repeating / Recurring / āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ: pattern repeatsāĨ¤ Ex: 0.181818…

  • Non-repeating / āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āύāĻšā§Ÿ: digits never repeat āĨ¤ Ex: 3.1415926…


Not Recurring Decimal / āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āύāĻšā§‹ā§ąāĻž āĻĻāĻļāĻŽāĻŋāĻ•


Major Points / āĻŽā§āĻ–ā§āϝ āĻŦāĻŋāώ⧟āϏāĻŽā§‚āĻš



  1. Digits do NOT repeat.āϏāĻ‚āĻ–ā§āϝāĻž āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āύāĻšā§ŸāĨ¤

  2. It can be: Terminating → ends // Non-terminating but non-repeating → goes on forever but no pattern


Examples / āωāĻĻāĻžāĻšā§°āĻŖ:



  1. Terminating | āĻļ⧇āώ āĻšā§‹ā§ąāĻž: 0.5, 0.75, 3.125

  2. Non-terminating but non-repeating | āĻļ⧇āώ āύāĻšā§Ÿ āĻ•āĻŋāĻ¨ā§āϤ⧁ āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āύāĻšā§Ÿ: 0.101001000100001…, √2 = 1.414213562…


Easy Way to Remember / āϏāĻšāĻœā§‡ āĻŽāύāϤ ā§°āĻžāĻ–āĻŋāĻŦāϞ⧈



  • Recurring Decimal / āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āĻĻāĻļāĻŽāĻŋāĻ•: Digits repeat in a fixed pattern. Ex: 0.272727… (27 keeps repeating)

  • Not Recurring Decimal | āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āύāĻšā§‹ā§ąāĻž āĻĻāĻļāĻŽāĻŋāĻ• : No digit repeats in a fixed pattern. Ex: 0.47

  • Terminating Decimal | āĻļ⧇āώ āĻšā§‹ā§ąāĻž āĻĻāĻļāĻŽāĻŋāĻ• : Stops after a limited number of digits. Ex: 1.25

  • Non-terminating Decimal | āĻļ⧇āώ āύāĻšā§‹ā§ąāĻž āĻĻāĻļāĻŽāĻŋāĻ• : Does not stop, goes on forever. Ex: 3.14…


Tricks | āĻŸā§ā§°āĻŋāĻ•āĻ›



  1. To check if a decimal is recurring → look for repeating digits.āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āĻĻāĻļāĻŽāĻŋāĻ• āϚāĻžāĻŦāϞ⧈ → āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āϏāĻ‚āĻ–ā§āϝāĻž āϚāĻžāĻ“āĻ•āĨ¤Ex: 0.727272… = recurring

  2. To convert recurring decimals to fractions: āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āĻĻāĻļāĻŽāĻŋāĻ•āĻ• āĻ­āĻ—ā§āύāĻžāĻ‚āĻļāϞ⧈ ā§°ā§‚āĻĒāĻžāĻ¨ā§āϤ⧰ āϕ⧰āĻž



  • 1-digit repeating → divide by 9

  • 2-digit repeating → divide by 99

  • 3-digit repeating → divide by 999



  1. If there is a non-repeating part before repeating starts:
    Assamese: āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤāĻŋ āφ⧰āĻŽā§āĻ­ āĻšā§‹ā§ąāĻžā§° āφāĻ—āϤ⧇ āϝāĻĻāĻŋ non-repeating āĻ…āĻ‚āĻļ āĻĨāĻžāϕ⧇ →
    Rule | āύāĻŋāϝāĻŧāĻŽ: Numerator = (all decimal digits) – (non-recurring digits) / Denominator = 9 for each repeating + 0 for each non-repeating


Important Rule (Exam Trick) / āϗ⧁⧰⧁āĻ¤ā§āĻŦāĻĒā§‚āĻ°ā§āĻŖ āύāĻŋāϝāĻŧāĻŽ (āĻĒāϰ⧀āĻ•ā§āώāĻž)



  1. A fraction is recurring if the denominator has prime factors other than 2 or 5
    Ex: 1/3 → recurring (has 3), 2/7 → recurring (has 7), 5/6 → recurring (has 3)



  1. A fraction is NOT recurring if denominator has only 2 or 5
    Ex: 1/4 → terminating (2) , 3/20 → terminating (2,5), 7/8 → terminating (2)




Summary of Decimals / āĻĻāĻļāĻŽāĻŋāϕ⧰ āϏāĻžāϰāĻžāĻ‚āĻļ


Recurring Decimal / āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āĻĻāĻļāĻŽāĻŋāĻ•: Meaning / āĻ…ā§°ā§āĻĨ: Repeats forever → can be written as fraction. Ex / āωāĻĻāĻžāĻšā§°āĻŖ: 1/3, 2/7


Not Recurring Decimal / āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āύāĻšā§‹ā§ąāĻž āĻĻāĻļāĻŽāĻŋāĻ• : Meaning / āĻ…ā§°ā§āĻĨ: No repeating pattern → terminating / irrational. Ex / āωāĻĻāĻžāĻšā§°āĻŖ: 0.47, √2


Terminating Decimal / āĻļ⧇āώ āĻšā§‹ā§ąāĻž āĻĻāĻļāĻŽāĻŋāĻ•: Meaning / āĻ…ā§°ā§āĻĨ: Stops after a finite number of digits. Ex / āωāĻĻāĻžāĻšā§°āĻŖ: 1.25


Non-terminating Repeating Decimal | āĻļ⧇āώ āύāĻšā§‹ā§ąāĻž āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āĻĻāĻļāĻŽāĻŋāĻ• : Meaning / āĻ…ā§°ā§āĻĨ: Decimal never ends, pattern repeats → recurring. Ex / āωāĻĻāĻžāĻšā§°āĻŖ: 0.272727…


Non-terminating Non-repeating Decimal | āĻļ⧇āώ āύāĻšā§‹ā§ąāĻž āĻĒ⧁āύ⧰āĻžāĻŦ⧃āĻ¤ā§āϤ āύāĻšā§‹ā§ąāĻž āĻĻāĻļāĻŽāĻŋāĻ•


    Meaning / āĻ…ā§°ā§āĻĨ: Decimal never ends, digits never repeat → irrational. Ex / āωāĻĻāĻžāĻšā§°āĻŖ: √2, π


Recurring Decimals to Fractions : Solution :  View Paper


Tricks : What is a Recurring Decimal & Not Recurring Decimal ? :  View Paper