One ball is drawn at random from a bag containing 2 red balls and 8 white balls.
(a) What is the probability that the ball is red?
Correct: Your answer is correct.
(b) What is the probability that the ball is green?
Correct: Your answer is correct.
(c) What is the probability that the ball is red or white?
Are we answering only c) ?
c) since there are only reds and whites, and you want prob(red OR white)
the prob(red OR white) = 1
that is, 2/10 + 8/10
= 10/10
= 1
To calculate the probability, we need to find the number of favorable outcomes and divide it by the total number of possible outcomes.
(a) To find the probability that the ball is red, we have 2 red balls and a total of 10 balls in the bag. So the number of favorable outcomes is 2 (the red balls) and the total number of possible outcomes is 10 (all the balls in the bag). Therefore, the probability of drawing a red ball is 2/10 or 1/5.
(b) To find the probability that the ball is green, we need to first determine if there are any green balls in the bag. Given that the only balls mentioned in the question are red and white, there are no green balls in the bag. Therefore, the probability of drawing a green ball is 0.
(c) To find the probability that the ball is red or white, we need to calculate the number of favorable outcomes for each color and add them together. As mentioned earlier, there are 2 red balls and 8 white balls in the bag. So, the number of favorable outcomes for red is 2 and for white is 8. The total number of possible outcomes is still 10. Therefore, the probability of drawing a red or white ball is (2 + 8)/10 or 10/10, which simplifies to 1.