human
Calculate the probability of two dependent events occurring without drawing a tree diagram There are \( 5 \) red balls and \( 4 \) yellow balls in a cup ![A cup with 5 red and 4 yellow balls in it. All of the balls are the same size.]() Kate picks out two balls at the same time.

What is the probability at least one ball is red? \( \frac{20}{72} \)
gpt
Does not work out all possibilites when given an 'at least' question in probability