Ex 14.1, 8 - Chapter 14 Class 10 Probability

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Ex 14.1, 8 (i) A bag contains 3 red balls and 5 black balls. A ball is drawn at random from the bag. What is the probability that the ball drawn is (i) red? Total number of balls in the bag = 5 + 3 = 8 Number of red balls = 3 Probability of getting a red ball = (𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑟𝑒𝑑 𝑏𝑎𝑙𝑙𝑠)/(𝑇𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑏𝑎𝑙𝑙𝑠) = 𝟑/𝟖 Ex 14.1, 8 (ii) (Method 1) A bag contains 3 red balls and 5 black balls. A ball is drawn at random from the bag. What is the probability that the ball drawn is (ii) not red? Total number of balls in the bag = 8 Probability of not getting a red ball = Probability of getting blackballs = (𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓𝑏𝑙𝑎𝑐𝑘 𝑏𝑎𝑙𝑙𝑠)/(𝑇𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑏𝑎𝑙𝑙𝑠) = 𝟓/𝟖 Ex 14.1, 8 (ii) (Method 2) A bag contains 3 red balls and 5 black balls. A ball is drawn at random from the bag. What is the probability that the ball drawn is (ii) not red? Probability of not getting red ball = 1 − Probability of getting a red ball = 1 – 3/8 = 𝟓/𝟖