Question #4f6e2

1 Answer

Solve a two equation 1 variable system with #x# = the original number as one equation, and create a second equation by multiplying the first by the power of #10# that has as many zeroes as the repeating decimal.

#4.bar(19) = 415/99#

Explanation:

Step 1: create 1st equation #x# = given number

#x = 4.19191919...#

Step 2: create 2nd equation by multiplying 1st equation by power of 10 with as many 0's as repeating digits
Here 2 repeating digits so multiply both sides by 100

#100x=419.19191919...#

Step 3: subtract 1st equ from second to eliminate decimal part ( both sides)

#" "100x=419.19191919...#
#- (" "x= " "4.19191919...)#
------------------------------
#" "99x=" "415#

Step 4
Solve for #x#

#x = 415/99 = 4.19191919...#

The answer in form of a fraction is #415/99# .