Question

What is cross multiplication helpful is?

Answer 1

In mathematics, specifically in elementary arithmetic and elementary algebra, given an equation between two fractions or rational expressions, one can cross-multiply to simplify the equation or determine the value of a variable.

Answer 2

Cross Multiplication is helpful for when you are using fractions.

Example:
1 4
— x — = ?????
2 2

Sooooo, you must multiply 1 by 2 to get 2. Then, multiply 4 by to 2, to equal 8.