Example 8 - Chapter 15 Class 10 Probability (Term 1)

Transcript

Example 8 A box contains 3 blue, 2 white, and 4 red marbles. If a marble is drawn at random from the box, what is the probability that it will be (i) white? Total number of marbles = 3 + 2 + 4 = 9 Number of marbles which are white = 2 P(marble taken out is white) = (𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑚𝑎𝑟𝑏𝑙𝑒𝑠 𝑤ℎ𝑖𝑐ℎ 𝑎𝑟𝑒 𝑤ℎ𝑖𝑡𝑒)/(𝑇𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑚𝑎𝑟𝑏𝑙𝑒𝑠) = 𝟐/𝟗 Example 8 A box contains 3 blue, 2 white, and 4 red marbles. If a marble is drawn at random from the box, what is the probability that it will be (ii) blue? Total number of marbles = 9 Number of marbles which are blue = 3 P(marble taken out is blue) = (𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑚𝑎𝑟𝑏𝑙𝑒𝑠 𝑤ℎ𝑖𝑐ℎ 𝑎𝑟𝑒 𝑏𝑙𝑢𝑒)/(𝑇𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑚𝑎𝑟𝑏𝑙𝑒𝑠) = 3/9 = 𝟏/𝟑 Example 8 A box contains 3 blue, 2 white, and 4 red marbles. If a marble is drawn at random from the box, what is the probability that it will be (iii) red? Total number of marbles = 9 Number of marbles which are red = 4 P(marble taken out is red) = (𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑚𝑎𝑟𝑏𝑙𝑒𝑠 𝑤ℎ𝑖𝑐ℎ 𝑎𝑟𝑒 𝑟𝑒𝑑)/(𝑇𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑚𝑎𝑟𝑏𝑙𝑒𝑠) = 𝟒/𝟗