# Find the other number when LCM and HCF given

Given a number **A** and L.C.M and H.C.F. The task is to determine the other number B.

Examples:

Input:A = 10, Lcm = 10, Hcf = 50.Output:B = 50Input:A = 5, Lcm = 25, Hcf = 4.Output:B = 20

**Formula:-**

A * B = LCM * HCF

B = (LCM * HCF)/AExample : A = 15, B = 12

HCF = 3, LCM = 60

We can see that 3 * 60 = 15 * 12.

How does this formula work?

Since HCF divides both the numbers, let.

A = HCF * x

B = HCF * yNote that x and y are not common factors, so LCM must include HCF, x and y.

So we can conclude.

LCM = HCF * x * ySo LCM * HCF = HCF * x * y * HCF which is equal to A * B

Below is the implementation of the above approach:

## C++

`// CPP program to find other number from given ` `// HCF and LCM ` `#include <bits/stdc++.h> ` `using` `namespace` `std; ` ` ` `// Function that will calculates ` `// the zeroes at the end ` `int` `otherNumber(` `int` `A, ` `int` `Lcm, ` `int` `Hcf) ` `{ ` ` ` `return` `(Lcm * Hcf) / A; ` `} ` ` ` `// Driver code ` `int` `main() ` `{ ` ` ` `int` `A = 8, Lcm = 8, Hcf = 1; ` ` ` ` ` `// Calling function. ` ` ` `int` `result = otherNumber(A, Lcm, Hcf); ` ` ` ` ` `cout << ` `"B = "` `<< result; ` ` ` ` ` `return` `0; ` `} ` |

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## Java

`// Java program to find other number from given ` `// HCF and LCM ` `class` `GFG{ ` ` ` `// Function that will calculates ` `// the zeroes at the end ` `static` `int` `otherNumber(` `int` `A, ` `int` `Lcm, ` `int` `Hcf) ` `{ ` ` ` `return` `(Lcm * Hcf) / A; ` `} ` ` ` `// Driver code ` `public` `static` `void` `main(String args[]) ` `{ ` ` ` `int` `A = ` `8` `, Lcm = ` `8` `, Hcf = ` `1` `; ` ` ` ` ` `// Calling function. ` ` ` `int` `result = otherNumber(A, Lcm, Hcf); ` ` ` ` ` `System.out.println(` `"B = "` `+ result); ` ` ` `} ` `} ` |

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## Python3

`# Python 3 program to find other ` `# number from given HCF and LCM ` ` ` `# Function that will calculates ` `# the zeroes at the end ` `def` `otherNumber(a, Lcm, Hcf): ` ` ` `return` `(Lcm ` `*` `Hcf) ` `/` `/` `A ` ` ` `# Driver code ` `A ` `=` `8` `; Lcm ` `=` `8` `; Hcf ` `=` `1` ` ` `# Calling function ` `result ` `=` `otherNumber(A, Lcm, Hcf) ` `print` `(` `"B ="` `, result) ` ` ` `# This code is contributed ` `# by Shrikant13 ` |

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## C#

`// C# program to find other number ` `// from given HCF and LCM ` `using` `System; ` ` ` `class` `GFG ` `{ ` ` ` `// Function that will calculates ` `// the zeroes at the end ` `static` `int` `otherNumber(` `int` `A, ` `int` `Lcm, ` ` ` `int` `Hcf) ` `{ ` ` ` `return` `(Lcm * Hcf) / A; ` `} ` ` ` `// Driver code ` `static` `public` `void` `Main(String []args) ` `{ ` ` ` `int` `A = 8, Lcm = 8, Hcf = 1; ` ` ` ` ` `// Calling function. ` ` ` `int` `result = otherNumber(A, Lcm, Hcf); ` ` ` ` ` `Console.WriteLine(` `"B = "` `+ result); ` `} ` `} ` ` ` `// This code is contributed by Arnab Kundu ` |

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## PHP

`<?php ` `// PHP program to find other number ` `// from given HCF and LCM ` ` ` `// Function that will calculates ` `// the zeroes at the end ` `function` `otherNumber(` `$A` `, ` `$Lcm` `, ` `$Hcf` `) ` `{ ` ` ` `return` `(` `$Lcm` `* ` `$Hcf` `) / ` `$A` `; ` `} ` ` ` `// Driver code ` `$A` `= 8; ` `$Lcm` `= 8; ` `$Hcf` `= 1; ` ` ` `// Calling function. ` `$result` `= otherNumber(` `$A` `, ` `$Lcm` `, ` `$Hcf` `); ` ` ` `echo` `"B = "` `. ` `$result` `; ` ` ` `// This code is contributed ` `// by Akanksha Rai ` |

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**Output:**

B = 1

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