Fraction Calculator - Calculation: 12 9/10-8 3/5

Fraction Calculator Enter fraction expression: 12 9/10-8 3/5 This fraction calculator performs all fraction operations - addition, subtraction, multiplication, and division — and evaluates expressions with fractions. Each calculation includes detailed step-by-step explanations.

The result:

12 9/10 - 8 3/5 = 43/10 = 4 3/10 = 4.3

Spelled out: forty-three tenths (or four and three tenths).

How do we solve fractions step by step?

1. Conversion a mixed number 12 9/10 to a improper fraction: 12 9/10 = 12 9/10 = 12 · 10 + 9/10 = 120 + 9/10 = 129/10To find a new numerator: a) Multiply the whole number 12 by the denominator 10. Whole number 12 equally 12 * 10/10 = 120/10 b) Add the answer from the previous step 120 to the numerator 9. New numerator is 120 + 9 = 129 c) Write a previous answer (new numerator 129) over the denominator 10.Twelve and nine tenths is one hundred twenty-nine tenths.
2. Conversion a mixed number 8 3/5 to a improper fraction: 8 3/5 = 8 3/5 = 8 · 5 + 3/5 = 40 + 3/5 = 43/5To find a new numerator: a) Multiply the whole number 8 by the denominator 5. Whole number 8 equally 8 * 5/5 = 40/5 b) Add the answer from the previous step 40 to the numerator 3. New numerator is 40 + 3 = 43 c) Write a previous answer (new numerator 43) over the denominator 5.Eight and three fifths is forty-three fifths.
3. Subtract: 129/10 - 43/5 = 129/10 - 43 · 2/5 · 2 = 129/10 - 86/10 = 129 - 86/10 = 43/10 It is suitable to adjust both fractions to a common (equal) denominator for subtracting fractions. The common denominator you can calculate as the least common multiple of both denominators - LCM(10, 5) = 10. It is enough to find the common denominator (not necessarily the lowest) by multiplying the denominators: 10 × 5 = 50. In the following intermediate step, it cannot further simplify the fraction result by canceling.In other words, one hundred twenty-nine tenths minus forty-three fifths equals forty-three tenths.

Rules for expressions with fractions:

Fractions - Use a forward slash to separate the numerator and denominator. For example, for five-hundredths, enter 5/100. Mixed numbers Leave one space between the whole number and the fraction part, and use a forward slash for the fraction. For example, enter 1 2/3 . For negative mixed numbers, write the negative sign before the whole number, such as -5 1/2. Division of fractions - Since the forward slash is used for both fraction lines and division, use a colon (:) to divide fractions. For example, to divide 1/2 by 1/3, enter 1/2 : 1/3. Decimals Enter decimal numbers using a decimal point (.), and they will be automatically converted to fractions. For example, enter 1.45.

Math Symbols

Symbol	Symbol name	Symbol Meaning	Example
+	plus sign	addition	1/2 + 1/3
-	minus sign	subtraction	1 1/2 - 2/3
*	asterisk	multiplication	2/3 * 3/4
×	times sign	multiplication	2/3 × 5/6
:	division sign	division	1/2 : 3
/	division slash	division	1/3 / 5
:	colon	complex fraction	1/2 : 1/3
^	caret	exponentiation / power	1/4^3
()	parentheses	calculate expression inside first	-3/5 - (-1/4)

Examples:

• adding fractions: 2/4 + 3/4• subtracting fractions: 2/3 - 1/2• multiplying fractions: 7/8 * 3/9• dividing fractions: 1/2 : 3/4• reciprocal of a fraction: 1 : 3/4• square of a fraction: 2/3 ^ 2• cube of a fraction: 2/3 ^ 3• exponentiation of a fraction: 1/2 ^ 4• fractional exponents: 16 ^ 1/2• adding fractions and mixed numbers: 8/5 + 6 2/7• dividing integer and fraction: 5 ÷ 1/2• complex fractions: 5/8 : 2 2/3• decimal to fraction: 0.625• fraction to decimal: 1/4• fraction to percent: 1/8 %• comparing fractions: 1/4 2/3• square root of a fraction: sqrt(1/16)• expression with brackets: 1/3 * (1/2 - 3 3/8)• compound fraction: 3/4 of 5/7• multiplying fractions: 2/3 of 3/5• divide to find the quotient: 3/5÷2/3 Order of Operations Ever wondered why calculators don't just work left to right? This calculator follows the mathematical order of operations — a set of rules that ensures everyone solves expressions the same way, every time. Popular Memory Tricks Different regions use different mnemonics to remember this order: * PEMDAS - Parentheses, Exponents, Multiplication, Division, Addition, Subtraction * BEDMAS - Brackets, Exponents, Division, Multiplication, Addition, Subtraction * BODMAS - Brackets, Order (or "Of"), Division, Multiplication, Addition, Subtraction * GEMDAS - Grouping symbols (parentheses, brackets, braces: (){}), Exponents, Multiplication, Division, Addition, Subtraction The Golden Rules Rule 1: Multiplication and division always come before addition and subtraction. Think of them as the VIPs that skip to the front of the line! Rule 2: When operations have equal priority (like × and ÷, or + and −), work from left to right—just like reading a book. Rule 3: Parentheses change the natural order of evaluation of operations.

Fractions in word problems:

• Closer to one Here are two sums: A=1/2 + 1/3 and B=1/5 + 1/3. Which of the two sums is closer in value to 1? You must show your work and state clearly whether the answer is A or B.
• Compare operators Place the correct symbol, < or >, between the two numbers: 4/7 and 5/6.
• The numerator The numerator of the fraction is 5 more than its denominator. If 4 is added to the numerator and denominator, the fraction obtained is 6/5. What is that fraction?
• Tourist route longest On the first day, tourists covered 3/14 of the planned route, on the second day 1/3 of the route, and on the third day 8/21 of the route. On which day did they walk the longest part of the route (1,2,3)?
• Fractions Sort fractions z1 = (20)/(9); z2 = (10)/(21); z3 = (15)/(14) by their size. The result writes as three serial numbers 1,2,3.
• Comparing by height Ira is 1 2/5 m tall. Her mother is 4/5 m as tall as Ira. How many times is Ira's mother taller than her?
• A laundry Mr. Green washed 1/4 of his laundry. His son washed 3/7 of it. Who washed most of the laundry? How much of the laundry still needs to be washed?

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Last Modified: February 17, 2026

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