why is the f distribution useful why do we use the f distribution why use f in probability why use a f distribution why use f distribution why use f distribution what is f distribution used for why is f useful for testing how can the f distribution be used for confidence interval estimation why is the probability distribution f used in this scenario why is an f distribution useful what would f be a good fit for why is the f distribution useful why use the f distribution what is the f distribution why is f used for probability why use f distribution why is an f distribution useful why use f distribution why use f distribution