There are 7 red skittles, 15 green skittles and 3 blue skittles in a bag.You reach into a bag and pick a skittle. You then put it back into the bag. You then reach into the bag and pick a skittle. What is the probability that you chose 2 green skittles? Reiny wrote prob(2 green)
= (15/25)(15/25)
= 9/25 but i don't get why
What part don't you understand ?
there are 25 skittles, of which 15 are green
so prob of green = 15/25 = 3/5
since you are returning the one you picked, the second prob is the same as the first
so prob(2green)
= (15/25)(15/25)
= (3/5)(3/5)
= 9/25
To calculate the probability of choosing two green skittles, you need to consider the total number of skittles in the bag and the number of green skittles.
In this case, there are a total of 7 red skittles, 15 green skittles, and 3 blue skittles in the bag, making a total of 7 + 15 + 3 = 25 skittles.
To calculate the probability of choosing a green skittle on the first pick, you have 15 green skittles out of 25 total skittles, so the probability is 15/25.
Since you put the first skittle back into the bag, the total number of skittles remains the same for the second pick. Therefore, the probability of choosing a green skittle on the second pick is also 15/25.
To find the probability of both events happening (choosing two green skittles), you multiply the probabilities of each individual event.
prob(2 green) = (15/25)(15/25) = 225/625 = 9/25
So the probability of choosing two green skittles is indeed 9/25.