Fractions
A fraction is a part of a whole: the numerator above the line, the denominator below. Calculate with two fractions and see the common denominator and the simplification step by step.
Your numbers
Answer
12+13=56
As a decimal
0.833333
As a percentage
83.3333 %
How to work it out
- 1Common denominator for 2 and 3: 6
- 21/2 = 3/6 1/3 = 2/6
- 33 + 2 = 5 → 5/6
The formula
a/b + c/d = (a·d + c·b) / (b·d)
Addition and subtraction: make the denominators the same first.
a/b · c/d = (a·c) / (b·d)
Multiplication: numerator times numerator, denominator times denominator.
a/b : c/d = a/b · d/c
Division: multiply by the reciprocal fraction.
a/b = (a:k) / (b:k)
Simplify: divide the numerator and denominator by the same number.
More: Numbers and percentages
- PercentPercentage of, how many per cent, percentage change, discount and VAT.
- Powers and rootsPowers, square roots, nth roots and numbers as powers of 10.
- Primes and divisorsIs it a prime? Prime factors, divisors, GCD and LCM.
- Rounding and estimatingRound to decimals, tens or significant figures — and make an estimate.
- Order of operationsEnter a calculation and see it worked out step by step in the right order.
- Number systems and Roman numeralsBinary, hexadecimal and Roman numerals — converted both ways with working.