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17/20 = 0.85000
Step 1:
Simplify 7/10
⇒ (3/4 + 4/5) - 7/10
Step 2:
Simplify 4/5
⇒ (3/4 + 4/5) - 7/10
Step 3:
Simplify 3/4
⇒(3/4 + 4/5) - 7/10
Step 4:
Calculating the Least Common Multiple
⇒ Find the Least Common Multiple
The left denominator is : Â Â Â 4 The right denominator is : Â Â Â 5
Number of times each prime factor
    appears in the factorization of:
Prime
Factor  Left
Denominator  Right
Denominator  L.C.M = Max
{Left,Right}
2202
5011
Product of all
Prime Factors  4520
 Least Common Multiple:
   20
Calculating Multipliers
⇒  Calculate multipliers for the two fractions
⇒  Denote the Least Common Multiple by  L.C.M
  ⇒ Denote the Left Multiplier by  Left_M
⇒  Denote the Right Multiplier by  Right_M
⇒   Denote the Left Deniminator by  L_Deno
⇒   Denote the Right Multiplier by  R_Deno
Left_M = L.C.M / L_Deno = 5 Right_M = L.C.M / R_Deno = 4Making Equivalent Fractions
⇒ Rewrite the two fractions into equivalent fractions
⇒ Two fractions are called equivalent if they have the same numeric value.
For example :  1/2  and  2/4  are equivalent,  y/(y+1)2  and  (y2+y)/(y+1)3  are equivalent as well.
To calculate equivalent fraction , multiply the Numerator of each fraction, by its respective Multiplier.
L. Mult. • L. Num.        3 • 5
  = Â
L.C.M Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â 20 Â
 R. Mult. • R. Num.    4 • 4
= Â
  L.C.M              20 Â
Adding fractions that have a common denominator
 Adding up the two equivalent fractions
Add the two equivalent fractions which now have a common denominator
Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:
3 • 5 + 4 • 4   31
= ---
   20      20
Equation at the end of step 4:
 31   7
-
20 Â 10
Step 5:
Calculating the Least Common Multiple :
 Find the Least Common Multiple
   The left denominator is :    20
   The right denominator is :    10
    Number of times each prime factor
    appears in the factorization of:
Prime
Factor  Left
Denominator  Right
Denominator  L.C.M = Max
{Left,Right}
2212
5111
Product of all
Prime Factors  201020
  Least Common Multiple:
   20
Calculating Multipliers :
Calculate multipliers for the two fractions
  Denote the Least Common Multiple by  L.C.M
  Denote the Left Multiplier by  Left_M
  Denote the Right Multiplier by  Right_M
  Denote the Left Deniminator by  L_Deno
  Denote the Right Multiplier by  R_Deno
Left_M = L.C.M / L_Deno = 1
 Right_M = L.C.M / R_Deno = 2
Making Equivalent Fractions :
Rewrite the two fractions into equivalent fractions
L. Mult. • L. Num.    31
=
L.C.M Â Â Â Â Â Â Â Â Â Â Â 20
R. Mult. • R. Num.    7 • 2
=
L.C.M Â Â Â Â Â Â Â 20 Â
Adding fractions that have a common denominator :
Adding up the two equivalent fractions
31 - (7 • 2)   17'
 = ---
20 Â Â Â Â Â 20
 17     Â
 —— = 0.85000
 20    Â
