How do you get the decimal equation for probability?

Answer 1

Find the total amount of possible outcomes, that's your denominator for the fraction, the bottom number, and find the amount of successes, that's your numerator, the top number. Turn the fraction into a decimal and that's your answer.

Answer 2

To obtain the decimal equation for probability, divide the number of favorable outcomes by the number of total possible outcomes. For example, if there are 5 favorable outcomes out of 20 total possible outcomes, the decimal equation for probability would be 5/20 = 0.25.