What is the ratio by which the cost price has to be multiplied to get the sale price, if the profit?

Profit is not a simple arithmetic expression. It involves cost, overhead, advertising, and other expenses.

Profit can be expressed as a percentage of something, but you have to say of what. "Percent" is a ruler with 100 marks. It's ok to measure profit and say it is ten of those marks, but that is only meaningful when you know what the marks are worth.

The ratio by which the cost price is multiplied is called "markup".