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BTGmoderatorLU
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in his ranch, Doug Bo can place a loop of rope, called a lasso, once in every two throws around a cow's neck. What is the probability that he will be able to place a lasso around a cow's neck at least once in 5 attempts?
(A) 1/5
(B) 15/32
(C) 1/2
(D) 31/32
(E) 1
The OA is D.
I solved this PS question as follow,
P( putting laaso) =1/2
P ( not putting lasso ) =1/2
Let's assume this person cannot put lasso around cows neck in 5 attempts : P = (1/2)^5=1/32
Then P ( putting lasso a least once) = 1 - (1/32)=31/32. Option D.
Experts, any suggestion? Thanks in advance.
(A) 1/5
(B) 15/32
(C) 1/2
(D) 31/32
(E) 1
The OA is D.
I solved this PS question as follow,
P( putting laaso) =1/2
P ( not putting lasso ) =1/2
Let's assume this person cannot put lasso around cows neck in 5 attempts : P = (1/2)^5=1/32
Then P ( putting lasso a least once) = 1 - (1/32)=31/32. Option D.
Experts, any suggestion? Thanks in advance.
