- 43/10 - 80/10 = ? Subtracting Ordinary (Simple, Common) Math Fractions Calculator, Subtraction Explained in Detail

The executed operation (with ordinary fractions):
- 43/10 - 80/10

Equal denominators fractions, work only with numerators:

- 43/10 - 80/10 =


( - 43 - 80)/10 =


- 123/10

Reduce (simplify) fraction to its lowest terms equivalent:

- 123/10 already reduced to the lowest terms.


The numerator and the denominator have no common prime factors.


Their prime factorization:


123 = 3 × 41;


10 = 2 × 5;

Reduce (simplify) fractions to their simplest form, online calculator


Rewrite the fraction

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

Mixed number = a whole number and a proper fraction, of the same sign.


Proper fraction = numerator smaller than denominator.


- 123 ÷ 10 = - 12 and remainder = - 3 =>


- 123 = - 12 × 10 - 3 =>


- 123/10 =


( - 12 × 10 - 3)/10 =


- 12 - 3/10 =


- 12 3/10

As a decimal number:

- 12 - 3/10 =


- 12 - 3 ÷ 10 =


- 12.3

As a percentage:

- 12.3 =


- 12.3 × 100/100 =


( - 12.3 × 100)/100 =


- 1,230/100 =


- 1,230%

>> Convert fractions to percentages, online calculator


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

As a negative improper fraction (numerator >= denominator):
- 43/10 - 80/10 = - 123/10

As a mixed number (also called a mixed fraction):
- 43/10 - 80/10 = - 12 3/10

As a decimal number:
- 43/10 - 80/10 = - 12.3

As a percentage:
- 43/10 - 80/10 = - 1,230%

How to subtract the ordinary fractions:
- 51/13 - 89/19

Writing numbers: comma ',' used as a thousands separator; point '.' used as a decimal mark;

Symbols: / fraction bar; ÷ divide; × multiply; + plus; - minus; = equal; ≈ approximation;

Add ordinary fractions, online calculator

The latest added fractions

- 43/10 - 80/10 = ? Jul 04 03:13 UTC (GMT)
18/4 + 6/25 = ? Jul 04 03:12 UTC (GMT)
1/247 + 36,148 = ? Jul 04 03:12 UTC (GMT)
1/36 + 1/18 + 1/36 = ? Jul 04 03:12 UTC (GMT)
56/42 + 36/54 = ? Jul 04 03:12 UTC (GMT)
61/2,213 - 171,139/11 = ? Jul 04 03:12 UTC (GMT)
8/60 + 8/12 = ? Jul 04 03:12 UTC (GMT)
4 - 3/5 = ? Jul 04 03:12 UTC (GMT)
1/20 + 1/30 + 1/42 + 1/56 + 1/72 + 1/90 + 1/110 + 1/132 = ? Jul 04 03:12 UTC (GMT)
519/60 - 10 = ? Jul 04 03:12 UTC (GMT)
109/9 + 10/10 = ? Jul 04 03:12 UTC (GMT)
11/28 + 2 = ? Jul 04 03:12 UTC (GMT)
- 17/28 + 16/35 = ? Jul 04 03:12 UTC (GMT)
see more... added fractions

How to: Adding ordinary (simple, common) math fractions. Steps.

There are two cases regarding the denominators when we add ordinary fractions:

  • A. the fractions have like denominators;
  • B. the fractions have unlike denominators.

A. How to add ordinary fractions that have like denominators?

  • Simply add the numerators of the fractions.
  • The denominator of the resulting fraction will be the common denominator of the fractions.
  • Reduce the resulting fraction.

An example of adding ordinary fractions that have like denominators, with explanations

  • 3/18 + 4/18 + 5/18 = (3 + 4 + 5)/18 = 12/18;

  • We simply added the numerators of the fractions: 3 + 4 + 5 = 12;
  • The denominator of the resulting fraction is: 18;
  • The resulting fraction is being reduced: 12/18 = (12 ÷ 6)/(18 ÷ 6) = 2/3.

  • How to reduce (simplify) the common fraction 12/18?

B. To add fractions with different denominators (unlike denominators), build up the fractions to the same denominator. How is it done?

  • 1. Reduce the fractions to the lowest terms (simplifying).

  • 2. Calculate the least common multiple, LCM, of all the fractions' new denominators:

    • LCM is going to be the common denominator of the added fractions.
    • Factor all the new denominators of the reduced fractions (run the prime factorization).
    • The least common multiple, LCM, is the product of all the unique prime factors of the denominators, taken by the largest exponents.
    • Calculate LCM, the least common multiple of numbers.

  • 3. Calculate each fraction's expanding number:

    • The expanding number is the non-zero number that will be used to multiply both the numerator and the denominator of each fraction, in order to build all the fractions up to the same common denominator.
    • Divide the least common multiple, LCM, calculated above, by each fraction's denominator, in order to calculate each fraction's expanding number.
  • 4. Expand each fraction:

    • Multiply each fraction's both numerator and denominator by expanding number.
    • At this point, fractions are built up to the same denominator.
  • 5. Add the fractions:

    • In order to add all the fractions simply add all the fractions' numerators.
    • The end fraction will have as a denominator the least common multiple, LCM, calculated above.
  • 6. Reduce the end fraction to the lowest terms, if needed.

... Read the rest of this article, here: How to add ordinary (common) fractions?

More on ordinary (common) math fractions theory: