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Cranes and Turtles Calculator

Solve the classic cranes-and-turtles word problem: find how many of each from the total heads and total legs, with a step-by-step solution and a check.

Input

Enter the total number of heads and legs to find how many cranes and turtles there are.

animals
legs

Leg counts default to 2 for cranes and 4 for turtles. Change them freely to count any two kinds of things.

legs
legs

Result

Answer

Cranes 3animals

Turtles 5animals

All turtles32Actual26

Head count check

3 plus 5 makes 8

Leg count check

2 times 3 plus 4 times 5 makes 26


How to solve it

1

If every animal were a turtle, the legs would total 4 times 8, which is 32.

2

The difference from the actual 26 legs is 26 minus 32, which is -6.

3

Swapping one turtle for one crane changes the legs by 4 minus 2, which is -2.

4

Dividing the difference -6 by -2 gives 3 cranes.

5

Subtracting 3 cranes from the 8 heads leaves 5 turtles.

How it works

  • Assume every animal is a turtle (the one with more legs) and compute the total legs for that case.
  • Find the difference between the assumed total and the actual number of legs.
  • Divide that difference by the gap in legs (turtle legs minus crane legs) to get the number of cranes.
  • Subtract the number of cranes from the total heads to get the number of turtles.
  • Leg counts default to 2 for cranes and 4 for turtles, but you can change them for any two-item problem.
  • If the numbers do not give a whole-number answer, the tool reports that there is no valid solution.

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