Ratio calculator

Ratios simplify by the greatest common divisor and scale by cross multiplication.

Simplified first term
2
= Exact Ratios
Simplified second term
5
As a single number
0.4
Second term when the first is scaled
15
First term as a share of the total
28.5714 %
Greatest common divisor
8
Show the working
  1. First term = 16
  2. Second term = 40
  3. Scale the first term to = 6
  4. Greatest common divisor = gcd(round(16), round(40)) = 8
  5. Simplified first term = 16 / 8 = 2
  6. Simplified second term = 40 / 8 = 5
  7. As a single number = 16 / 40 = 0.4
  8. Second term when the first is scaled = 6 * 40 / 16 = 15
  9. First term as a share of the total = 16 / (16 + 40) * 100 = 28.5714

Values are shown to six significant figures here; the arithmetic itself runs on exact fractions and is only rounded where a number is printed.

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    The formula

    • a : b simplifies by dividing both by gcd(a, b)
    • If a : b = c : d then d = c b / a

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