Question

44) Three coins are tossed simultaneously 150 times with the following frequencies of different outcomes.

Number of tails 0 1 2 3

Frequency 25 30 32 63

Compare the probability of getting

(i) at least 2 tails (ii) exactly 1 tail (iii) at most 3 tails.
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Answer 1

★FIND:

Probability of getting ;

(i) at least 2 tails (ii) exactly 1 tail (iii) at most 3 tails.

★Given,

=> three coins are tossed simultaneously 150 times with the following frequencies of different outcomes.

=>No. of tails :- 0, 1 , 2, 3

=>Frequency:- 25, 30, 32, 63

★SOLUTION:

$p(E) \frac{no. \: of \: \: favourable \: outcomes \: }{total \: number \: of \: outcomes}$

★i) let F be the event getting "at least 2 tails"

➡️ P(2 tail) + P(3 tail)

➡️ 32/150 + 63/150

➡️ (32 + 63)/150

P(F) =n(f)/n(s)

➡️ 95/150

➡️19/30

★ii)let E be the event getting a "exactly 1 tail"

P(E) =$\frac{n(e)}{n(s)}$

➡️ 30/150

➡️1/5

iii) let G be the event getting a"at most 3 tail"

➡️P(0 tail) + P(1 tail) + P(2 tail) + P(3 tail)

➡️25/150 + 30/150 + 32/150 + 63/150

➡️(25 + 30 + 32 + 63)/150

P(g) =n(g)/n(s)

➡️150/150

➡️1