Running, or linear meter, is a term often used in fabric manufacturing. For a roll of fabric, the price is given for the running meter, and the width of the roll is known. The task is to calculate the price of fabric slice of a certain length and width, given the running meter's price and the width of the roll.
Actually, the formula is simple - find the price of a square centimeter, then multiply it by slice square, that is
Update: After reading the comments, I've decided to add a square meter price to the output.
Below is the calculator