Answer to Question #21933 in Statistics and Probability for jamer binuya
"a box contain 500 envelops for prizes of different categories of which 75 contains 500php in cash, 150 contain 250php and 275 contain 100php. an envelope may be purchased for 250php. what is the sample space for the different mount of money? assign probability to sample points and then find the probability that the first envelope purchased contains less than 500php. With solution".
Total amount of envelopes is 500, total amount of envelopes which contain 500 php is 75. Thus we can calculate probability that first envelope chosen will contain less than 500 php Probability=(500-75)/500=85% Sample space for the different amount of money is 3, because there are 3 possible variants of envelopes.
If only 2 envelopes are chosen then the sample space consists of pairs (a, b), where a, b belong to one of three types of envelopes (500 php, 250 php, 100 php). The probability of the sum of both to be under 100 php is zero because the value of each envelope is greater than or equal to 100 php.
What if someone were to pick 2 envelopes. What would be the probability of the sum of both to be under 100$?