# 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 = 50

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

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Formula:-

A * B = LCM * HCF
B = (LCM * HCF)/A

Example : 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 * y

Note that x and y are not common factors, so LCM must include HCF, x and y.
So we can conclude.
LCM = HCF * x * y

So 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 ` `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; ` `} `

## 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);  ` ` `  `} ` `}  `

## 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 `

## 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 `

## PHP

 `

Output:

```B = 1
```

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