A bag contains 4 green marbles, 9 red marbles, 10 orange marbles, 9 brown marbles, and 11 blue marbles. You choose a marble, replace it, and choose again. What is P (red, then blue)
This is my question that I have on my 8th grade pre-algebra homework and I was sick today at school so I was wondering how do I do this?
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$\begingroup$Have you tried to solve this problem yourself? It is a very elementary probability question that can be answered using the rule of product, which states that if there are $n$ ways of an event happening and $m$ ways of another event happening, there are $n \cdot m$ ways of both events happening.
The probability of the first marble being red is $\frac{9}{43}$. After returning this marble to the bag, the probability of the second marble being blue is $\frac{11}{43}$. So the probability picking a red marble, and then a blue marble is $\frac{9}{43} \cdot \frac{11}{43} \approx 0.054$.
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