343/120 + 324/144 - 290/145 + 313/127 + 346/127 - 335/133 - 357/127 - 315/140 + 300/19 = ? Adding Up Common (Ordinary) Fractions, Online Calculator. Addition Operation Explained Step by Step

Fractions' addition: 343/120 + 324/144 - 290/145 + 313/127 + 346/127 - 335/133 - 357/127 - 315/140 + 300/19 = ?

Simplify the operation

These fractions have equal denominators (the same denominator):

  • This is the simplest and happiest case when we add or subtract fractions.
  • We work only with their numerators and keep the common denominator.

313/127 + 346/127 - 357/127 = 302/127

Rewrite the equivalent simplified operation:

343/120 + 324/144 - 290/145 + 313/127 + 346/127 - 335/133 - 357/127 - 315/140 + 300/19 =


343/120 + 324/144 - 290/145 - 335/133 - 315/140 + 300/19 + 302/127

Reduce (simplify) the fractions to their lowest terms equivalents:

  • To reduce a fraction to its lowest terms equivalent: divide the numerator and denominator by their greatest common factor, GCF.
  • * Why do we reduce (simplify) the fractions?
  • By reducing the values of the numerators and denominators of fractions, further calculations with these fractions become easier to do.
  • A fraction that was reduced (simplified) to the lowest terms is one with the smallest possible numerator and denominator, one that can no longer be reduced, and it is called an irreducible fraction.

* * *

The fraction: 343/120

343/120 is already reduced to the lowest terms.


  • The numerator and denominator have no common prime factors.
  • Their prime factorization:
  • 343 = 73
  • 120 = 23 × 3 × 5
  • GCF (73; 23 × 3 × 5) = 1

The fraction: 324/144

  • The prime factorizations of the numerator and denominator:
  • 324 = 22 × 34
  • 144 = 24 × 32
  • Multiply all the common prime factors: if there are repeating prime factors we only take them once, and only the ones having the lowest exponent (the lowest powers).
  • GCF (324; 144) = 22 × 32 = 36

324/144 = (324 ÷ 36)/(144 ÷ 36) = 9/4


  • Yet another method to simplify the fraction:

  • Without calculating GCF, factor the numerator and denominator and cross out all the common prime factors.
  • 324/144 = (22 × 34)/(24 × 32) = ((22 × 34) ÷ (22 × 32 ))/((24 × 32) ÷ (22 × 32 )) = 9/4


The fraction: - 290/145

  • 290 = 2 × 5 × 29
  • 145 = 5 × 29
  • GCF (290; 145) = 5 × 29 = 145

- 290/145 = - (290 ÷ 145)/(145 ÷ 145) = - 2/1 = - 2


  • We could have simplified the fraction without calculating the GCF. Just factor the numerator and denominator and cross out the common prime factors.
  • - 290/145 = - (2 × 5 × 29)/(5 × 29) = - ((2 × 5 × 29) ÷ (5 × 29))/((5 × 29) ÷ (5 × 29)) = - 2/1 = - 2


The fraction: - 335/133

- 335/133 is already reduced to the lowest terms.


  • The numerator and denominator have no common prime factors.
  • Their prime factorization:
  • 335 = 5 × 67
  • 133 = 7 × 19
  • GCF (5 × 67; 7 × 19) = 1

The fraction: - 315/140

  • 315 = 32 × 5 × 7
  • 140 = 22 × 5 × 7
  • GCF (315; 140) = 5 × 7 = 35

- 315/140 = - (315 ÷ 35)/(140 ÷ 35) = - 9/4


  • We could have simplified the fraction without calculating the GCF. Just factor the numerator and denominator and cross out the common prime factors.
  • - 315/140 = - (32 × 5 × 7)/(22 × 5 × 7) = - ((32 × 5 × 7) ÷ (5 × 7))/((22 × 5 × 7) ÷ (5 × 7)) = - 9/4


The fraction: 300/19

300/19 is already reduced to the lowest terms.


  • The numerator and denominator have no common prime factors.
  • Their prime factorization:
  • 300 = 22 × 3 × 52
  • 19 is a prime number
  • GCF (22 × 3 × 52; 19) = 1

The fraction: 302/127

302/127 is already reduced to the lowest terms.


  • The numerator and denominator have no common prime factors.
  • Their prime factorization:
  • 302 = 2 × 151
  • 127 is a prime number
  • GCF (2 × 151; 127) = 1


Rewrite the equivalent simplified operation:

343/120 + 324/144 - 290/145 - 335/133 - 315/140 + 300/19 + 302/127 =


343/120 + 9/4 - 2 - 335/133 - 9/4 + 300/19 + 302/127 =


- 2 + 343/120 + 9/4 - 335/133 - 9/4 + 300/19 + 302/127

These fractions cancel each other out:

The absolute values are equal but the signs are different.

The fractions: 9/4 and - 9/4;


Rewrite the equivalent simplified operation:

- 2 + 343/120 + 9/4 - 335/133 - 9/4 + 300/19 + 302/127 =


- 2 + 343/120 - 335/133 + 300/19 + 302/127

Rewrite the improper fractions:

  • An improper fraction: the value of the numerator is larger than or equal to the value of the denominator.
  • A proper fraction: the value of the numerator is smaller than the value of the denominator.
  • Each improper fraction will be rewritten as a whole number and a proper fraction, both having the same sign: divide the numerator by the denominator and write down the quotient and the remainder of the division, as shown below.
  • Why do we rewrite the improper fractions?
  • By reducing the value of the numerator of a fraction the calculations are getting easier to perform.
* * *

The fraction: 343/120


343 ÷ 120 = 2 and the remainder = 103 ⇒ 343 = 2 × 120 + 103


343/120 = (2 × 120 + 103)/120 = (2 × 120)/120 + 103/120 = 2 + 103/120


The fraction: - 335/133


- 335 ÷ 133 = - 2 and the remainder = - 69 ⇒ - 335 = - 2 × 133 - 69


- 335/133 = ( - 2 × 133 - 69)/133 = ( - 2 × 133)/133 - 69/133 = - 2 - 69/133


The fraction: 300/19


300 ÷ 19 = 15 and the remainder = 15 ⇒ 300 = 15 × 19 + 15


300/19 = (15 × 19 + 15)/19 = (15 × 19)/19 + 15/19 = 15 + 15/19


The fraction: 302/127


302 ÷ 127 = 2 and the remainder = 48 ⇒ 302 = 2 × 127 + 48


302/127 = (2 × 127 + 48)/127 = (2 × 127)/127 + 48/127 = 2 + 48/127



Rewrite the equivalent simplified operation:

- 2 + 343/120 - 335/133 + 300/19 + 302/127 =


- 2 + 2 + 103/120 - 2 - 69/133 + 15 + 15/19 + 2 + 48/127 =


15 + 103/120 - 69/133 + 15/19 + 48/127

Perform the operation of calculating the fractions.

To add or subtract fractions we need them to have equal denominators (the same common denominator).

  • To perform the operation of calculating the fractions we have to:
  • 1) find their common denominator
  • 2) then calculate the expanding number of each fraction
  • 3) then make their denominators the same by expanding the fractions to equivalent forms - which all have equal denominators (the same denominator)

  • * The common denominator is nothing else than the least common multiple (LCM) of the denominators of the fractions.
  • The LCM will be the common denominator of the fractions that we work with.

1) Find the common denominator
Calculate the LCM of the denominators:

The prime factorization of the denominators:


120 = 23 × 3 × 5


133 = 7 × 19


19 is a prime number


127 is a prime number


Multiply all the unique prime factors: if there are repeating prime factors we only take them once, and only the ones having the highest exponent (the highest powers).

LCM (120; 133; 19; 127) = 23 × 3 × 5 × 7 × 19 × 127 = 2,026,920



2) Calculate the expanding number of each fraction:

Divide the LCM by the denominator of each fraction.


103/120 ⟶ 2,026,920 ÷ 120 = (23 × 3 × 5 × 7 × 19 × 127) ÷ (23 × 3 × 5) = 16,891


- 69/133 ⟶ 2,026,920 ÷ 133 = (23 × 3 × 5 × 7 × 19 × 127) ÷ (7 × 19) = 15,240


15/19 ⟶ 2,026,920 ÷ 19 = (23 × 3 × 5 × 7 × 19 × 127) ÷ 19 = 106,680


48/127 ⟶ 2,026,920 ÷ 127 = (23 × 3 × 5 × 7 × 19 × 127) ÷ 127 = 15,960


3) Make fractions' denominators the same:

  • Expand each fraction: multiply both its numerator and denominator by its corresponding expanding number, calculated at the step 2, above. This way all the fractions will have the same denominator.
  • Then keep the common denominator and work only with the numerators of the fractions.

15 + 103/120 - 69/133 + 15/19 + 48/127 =


15 + (16,891 × 103)/(16,891 × 120) - (15,240 × 69)/(15,240 × 133) + (106,680 × 15)/(106,680 × 19) + (15,960 × 48)/(15,960 × 127) =


15 + 1,739,773/2,026,920 - 1,051,560/2,026,920 + 1,600,200/2,026,920 + 766,080/2,026,920 =


15 + (1,739,773 - 1,051,560 + 1,600,200 + 766,080)/2,026,920 =


15 + 3,054,493/2,026,920


Reduce (simplify) the fraction to its lowest terms equivalent:

3,054,493/2,026,920 is already reduced to the lowest terms.

The numerator and denominator have no common prime factors.


  • Their prime factorization:
  • 3,054,493 = 13 × 234,961
  • 2,026,920 = 23 × 3 × 5 × 7 × 19 × 127
  • GCF (13 × 234,961; 23 × 3 × 5 × 7 × 19 × 127) = 1


Rewrite the result

As a positive improper fraction:
(the numerator >= the denominator)

  • An improper fraction: the value of the numerator is larger than or equal to the value of the denominator.

15 + 3,054,493/2,026,920 =


(15 × 2,026,920)/2,026,920 + 3,054,493/2,026,920 =


(15 × 2,026,920 + 3,054,493)/2,026,920 =


33,458,293/2,026,920

As a mixed number (also called a mixed fraction):

  • A mixed number: a whole number and a proper fraction, both having the same sign.
  • A proper fraction: the value of the numerator is smaller than the value of the denominator.
  • Divide the numerator by the denominator and write down the quotient and the remainder of the division, as shown below:

33,458,293 ÷ 2,026,920 = 16 and the remainder = 1,027,573 ⇒


33,458,293 = 16 × 2,026,920 + 1,027,573 ⇒


33,458,293/2,026,920 =


(16 × 2,026,920 + 1,027,573)/2,026,920 =


(16 × 2,026,920)/2,026,920 + 1,027,573/2,026,920 =


16 + 1,027,573/2,026,920 =


16 1,027,573/2,026,920

As a decimal number:

Simply divide the numerator by the denominator, without a remainder, as shown below:


16 + 1,027,573/2,026,920 =


16 + 1,027,573 ÷ 2,026,920 ≈


16.506962780968 ≈


16.51

As a percentage:

  • A percentage value p% is equal to the fraction: p/100, for any decimal number p. So, we need to change the form of the number calculated above, to show a denominator of 100.
  • To do that, multiply the number by the fraction 100/100.
  • The value of the fraction 100/100 = 1, so by multiplying the number by this fraction the result is not changing, only the form.

16.506962780968 =


16.506962780968 × 100/100 =


(16.506962780968 × 100)/100 =


1,650.696278096817/100


1,650.696278096817% ≈


1,650.7%



The final answer:
:: written in four ways ::

As a positive improper fraction:
(the numerator >= the denominator)
343/120 + 324/144 - 290/145 + 313/127 + 346/127 - 335/133 - 357/127 - 315/140 + 300/19 = 33,458,293/2,026,920

As a mixed number (also called a mixed fraction):
343/120 + 324/144 - 290/145 + 313/127 + 346/127 - 335/133 - 357/127 - 315/140 + 300/19 = 16 1,027,573/2,026,920

As a decimal number:
343/120 + 324/144 - 290/145 + 313/127 + 346/127 - 335/133 - 357/127 - 315/140 + 300/19 ≈ 16.51

As a percentage:
343/120 + 324/144 - 290/145 + 313/127 + 346/127 - 335/133 - 357/127 - 315/140 + 300/19 ≈ 1,650.7%

How are the numbers written: comma ',' used as a thousands separator; point '.' as a decimal separator; numbers rounded off to max. 12 decimals (if the case). The symbols used: '/' fraction bar; ÷ dividing; × multiplying; + plus (adding); - minus (subtracting); = equal; ≈ approximately equal.

Other similar operations:

How to add the common ordinary fractions:
- 348/128 - 336/152 - 295/150 - 319/134 + 352/136 - 346/137 + 368/135 + 325/149 + 308/26

Add common ordinary fractions, online calculator:

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