if from a lottery of 30tickets, marked 1to 30,4 tickets are drawn . what is the probability that those marked 1 and 2 are among them ?
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18
if you know permutation and combination, the answer is simple:
Of the four tickets, two have to be 1 and 2 and the other two can be any one of the other 28 tickets.
if order of tickets drawn is not important, favourable number of ways is 28 C 2.
if order is important, the favourable number of ways is 4! * 28 C 2.
For probability, divide the favourable number of ways by total number of ways of choosing 4 tickets, I.e. 30 P 2 or 30 C 2 depending on whether order is or isn't important
Of the four tickets, two have to be 1 and 2 and the other two can be any one of the other 28 tickets.
if order of tickets drawn is not important, favourable number of ways is 28 C 2.
if order is important, the favourable number of ways is 4! * 28 C 2.
For probability, divide the favourable number of ways by total number of ways of choosing 4 tickets, I.e. 30 P 2 or 30 C 2 depending on whether order is or isn't important
Answered by
7
Answer:
Step-by-step explanation:
P (A)=28C2/30C4
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