A bowl contains 4 yellow marbles and 3 red marbles. Eric randomly draws 3 marbles from the bowl. He replaces each marble after it is drawn. What is the probability that he draws 1 yellow marble and 2 red marbles? @dabest21
well the first probability is 4/7 (4 yellow out of seven total). then he picks one and REPLACES IT (key words) this means the total marbles wont change so do 4/7*3/7*3/7 in other words do 4*3*3=what @thisotherliz
36
yes now 7*7*7=what @thisotherliz
343
yes so 36/343
for further problems know that if it doesn't say he/she replaced whatever item was took out then make it into fractions with the total going down each time its like if u had 5 cookies and u ate 1 u wouldn't still have 5 u would have 4 so that would at first be 5/5 (because they are all cookies) then for the second cookie its 4/4 if it says it was replaced just don't change the total amount Plz ask me for more help but also read all of this @thisotherliz
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