Q. 19
In a hurdles race, a player has to cross 10 hurdles. The probability that he will clear each hurdle is (5/6). What is the probability that he will knock down fewer than 2 hurdles?
Answer :
The probability that the hurdle will be cleared is 5/6
Using Bernoulli’s Trial we have,
P(Success=x) = nCx.px.q(n-x)
x=0, 1, 2, ………n and q = (1-p), n =10
p = 5/6 q = 1/6
Probability that he will knock down fewer than 2 hurdles is =
P(0) + P(1)
⇒ 10C0(
)0(
)10 + 10C1(
)1(
)9
⇒ 
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