CLASS-7
RECURRING DECIMALS

RECURRING DECIMALS:-

A recurring decimal (also called a repeating decimal) is a decimal fraction that has a digit or a sequence of digits that repeats infinitely. These decimals can be represented in two ways:

  1. As a bar notation:- For example, 0.333… is written as 0.3‾, where the bar ( ) indicates that the digit 3 repeats indefinitely.

  2. As a fraction:-  Every recurring decimal can be expressed as a fraction of two integers (a rational number). 

                                1                       4

       For example, 0.3‾= ------  and 0.12‾= -------

                                3                      33


How to Convert a Recurring Decimal to a Fraction:-

Here's the general process for converting:

Example 1: Single Digit Repeats (0.6‾)

Ans.)

Step.1:-    Let x = 0.6‾.

Step.2:-  Multiply both sides by 10 to shift the repeating part:

                10x = 6.6‾ X 10

Step.3:-  Subtract the original equation:

             (10x − x)  =  (6.6‾− 0.6‾)

                              6          2

Step.4:-  Solve for x = ------ = ------

                              9          3

decimal

Example 2: Multiple Digits Repeat (0.123‾)

Ans.)

Step.1:- Let x = 0.123‾

Step.2:-  Multiply by 10ⁿ, where n is the number of repeating digits (here n = 3):

                     1000x = 123.123‾   

Step.3:-  Subtract the original equation:

                     1000x − x = 123.123‾ − 0.123‾

                giving,  999x = 123

                               123          41

Step.4:-  Solve for  x = -------- = -------

                               999         333