Ex 15.1, 13 - Class 10

Transcript

Ex15.1, 13 A die is thrown once. Find the probability of getting (i) a prime number; Total outcomes that can occur are 1, 2, 3, 4, 5, 6 Number of possible outcomes of a dice = 6 Prime number is a number not divisible by any number except itself Prime numbers on a dice are 2, 3, and 5. Total prime numbers on a dice = 3 Probability of getting a prime number = (𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑜𝑢𝑡𝑐𝑜𝑚𝑒𝑠 𝑤ℎ𝑒𝑟𝑒 𝑝𝑟𝑖𝑚𝑒 𝑛𝑢𝑚𝑏𝑒𝑟 𝑐𝑜𝑚𝑒𝑠)/(𝑇𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑜𝑢𝑡𝑐𝑜𝑚𝑒𝑠) = 3/6 = 1/2 Ex15.1, 13 A die is thrown once. Find the probability of getting (ii) a number lying between 2 and 6; Total outcomes that can occur are 1, 2, 3, 4, 5, 6 Number of possible outcomes of a dice = 6 Numbers lying between 2 and 6 = 3, 4, 5 Total numbers lying between 2 and 6 = 3 Probability of getting a number lying between 2 & 6 = (𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑜𝑢𝑡𝑐𝑜𝑚𝑒𝑠 𝑤ℎ𝑒𝑟𝑒 𝑡ℎ𝑒𝑟𝑒 𝑖𝑠 𝑎 𝑛𝑢𝑚𝑏𝑒𝑟 𝑏𝑒𝑡𝑤𝑒𝑒𝑛 2 & 6)/(𝑇𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑜𝑢𝑡𝑐𝑜𝑚𝑒𝑠) = 3/6 = 1/2 Ex15.1, 13 A die is thrown once. Find the probability of getting (iii) an odd number. Total outcomes that can occur are 1, 2, 3, 4, 5, 6 Number of possible outcomes of a dice = 6 Numbers which are odd = 1,3, 5 Total numbers which are odd = 3 Probability of getting an odd number = (𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑜𝑢𝑡𝑐𝑜𝑚𝑒𝑠 𝑤ℎ𝑒𝑟𝑒 𝑡ℎ𝑒𝑟𝑒 𝑖𝑠 𝑎𝑛 𝑜𝑑𝑑 𝑛𝑢𝑚𝑏𝑒𝑟)/(𝑇𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑜𝑢𝑡𝑐𝑜𝑚𝑒𝑠) = 3/6 = 1/2